

InterviewSolution
This section includes InterviewSolutions, each offering curated multiple-choice questions to sharpen your knowledge and support exam preparation. Choose a topic below to get started.
51. |
Intercept form of a line is …………….A) \(\cfrac{x}{a}\) + \(\cfrac{y}{b}\) = 1B) x – y = 7C) \(\cfrac{x}{a}\) - \(\cfrac{y}{b}\) = 1D) y = mx + c |
Answer» Correct option is (A) \(\frac{x}{a} + \frac{y}{b} = 1\) \(\frac{x}{a} + \frac{y}{b} = 1\) is intercept form a line. Correct option is A) \(\cfrac{x}{a}\) + \(\cfrac{y}{b}\) = 1 |
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52. |
What is the equation of the line having the y-intercept –1 and parallel to the line y = 5x – 7 ? |
Answer» Comparing y = 5\(x\) –7 with y = m\(x\) + c, the slope of given line = m = 5 ∴ Equation of a line parallel to y = 5\(x\) – 7 having y-intercept = –1 is y = 5\(x\) – 1. |
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53. |
If the points P (x, y) is equidistant from the points A (5, 1) and B (-1, 5), prove that 3x = 2y. |
Answer» Since P (x, y) is equidistant from A (5, 1) and B (-1, 5), then PA = PB or PA2 = PB2 (5 – x)2 + (1 – y)2 = (– 1 – x)2 + (5 – y)2 (25 + x2 – 10x) + (1 + y2 – 2y) = (1 + x2 + 2x + 25 + y2 – 10y) 26 + x2 – 10x + y2 – 2y = (26 + x2 + 2x + y2 – 10y) 12x = 8y 3x = 2y Hence proved. |
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54. |
If P (x, y) is a point equidistant from the points A(6, -1) and B(2, 3), show that x – y = 3. |
Answer» Since P (x, y) is equidistant from A(6, -1) and B(2, 3), then PA = PB or PA2 = PB2 (6 – x)2 + (-1 – y)2 = (2 – x)2 + (3 – y)2 (36 + x2 – 12x) + (1 + y2 + 2y) = (4 + x2 – 4x + 9 + y2 – 6y) 37 – 12x + 2y = 13 – 4x – 6y 8x = 8y + 24 x – y = 3 Hence proved. |
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55. |
The slope of a line perpendicular to the line which passes through the points (–k, h) and (b, – f ) is(a) –1 (b) \(\frac{f-h}{b+k}\)(c) \(\frac{b+k}{f+h}\)(d) \(\frac{-b+k}{f-h}\) |
Answer» (c) \(\frac{b+k}{f+h}\) Let the slope of the lin passing through the points (–k, h) and (b, – f) be m1. Then m1 = \(\frac{-f-h}{b+k}\) = \(-\bigg(\frac{f+h}{b+k}\bigg)\) \(\bigg[Slope = \frac{y_2-y_1}{x_2-x_1}\bigg]\) ∴ Slope of line perpendicular to the given line = \(-\frac{1}{m_1}\) = \(\frac{-1}{-\big(\frac{f+h}{b+k}\big)}\) = \(\bigg(\frac{b+k}{f+h}\bigg)\) |
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56. |
Re state the following statement with appropriate conditions to make it true statement. “For every real number x, x2 ≥ x”. |
Answer» If x ≤ 0 or x ≥ 1 then x2 ≥ x. For every integer x, x2 ≥ x. |
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57. |
Among the points given below, some of the points lie on X - axis. Identify them. i) (0, 5) ii) (0, 0) iii) (3, 0) iv) (- 5, 0) v) (- 2, – 3) vi) (- 6,0) vii)(0,6) viii)(0, a) ix) (b, 0) |
Answer» The points (ii) (0, 0), (iii) (3, 0) (iv) (- 5, 0) (vi) (- 6, 0) and (ix) (b, 0) lie on X – axis. |
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58. |
Look at the graph. Write the co-ordinates of the points A, B, C, D, E, F. G. H, 1, J, K, L, M, N, O, P and Q. |
Answer» A(- 3, 4) ; B(0, 5) : C (3, 4) ; D (2, 4) ; E (2, 0) ; F (3, 0) ; G (3, – 1) ; H (0, – 1) ; I (- 3, – 1) ; J (- 3, 0) ; K (- 2, 0) ; L (- 2, 4) ; M (- 1, 0) ; N (-1, 3); O (0, 0) ; P (1. 3) and Q (1, 0) |
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59. |
The co-ordinates of a point M(4, – 3). What are the distances of the point M from axes? |
Answer» Given point = M(4, -3) Distance from x -axis to the M is | -3 | units = 3 Distance from y – axis to the M is | 4 | units = 4 |
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60. |
i) Write the co-ordinates of the points A, B, C, D and E.ii) Write the co-ordinates of F, G, H, I and J. |
Answer» i) A(2, 9) ; B(5, 9); C(2, 6) ; D(5, 3) ; E(2, 3) ii) F(- 6, – 2) ; G(- 4, – 5) ; H(- 3, – 7) ; I(- 9, – 7) ; J(- 8, – 5) |
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61. |
In the graph alongside, line LM is parallel to the Y-axis.i. What is the distance of line LM from the Y-axis? ii. Write the co-ordinates of the points P, Q and R.iii. What is the difference between the x co-ordinates of the points L and M? |
Answer» i. Distance of line LM from the Y-axis is 3 units. ii. P(3, 2), Q (3, -1), R(3, 0) iii. x co-ordinate of point L = 3 x co-ordinate of point M = 3 ∴ Difference between the x co-ordinates of the points L and M = 3 – 3 = 0 |
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62. |
Without plotting the points on a graph, state in which quadrant or on which axis do the following points lie. i. (5, -3) ii. (-7, -12) iii. (-23, 4) iv. (-9, 5) v. (0, -3)vi. (-6, 0) |
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Answer» Quadrant Position
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63. |
In which quadrant or on which axis each of the following points lie?(-3, 5), (4,-1), (2,0), (2, 2), (-3,-6) |
Answer» (i) In point (-3, 5), x-coordinate is negative and y-coordinate is positive, so it lies in (ii) In point (4,-1), x-coordinate is positive and y-coordinate is negative, so it lies in IV quadrant. (iii) In point (2,0), x-coordinate is positive and y-coordinate is zero, so it lies on X-axis. (iv) In point (2,2), x-coordinate and y-coordinate both are positive, so it lies in I quadrant. (v) In point (-3, – 6), x-coordinate and y-coordinate both are negative, so it lies in III quadrant. |
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64. |
Without plotting the points indicate the quadrant in which they will lie, if(i) ordinate is 5 and abscissa is – 3(ii) abscissa is – 5 and ordinate is – 3(iii) abscissa is – 5 and ordinate is 3(iv) ordinate is 5 and abscissa is 3 |
Answer» (i) The point is (-3,5). Hence, the point lies in the II quadrant. (ii) The point is (-5,-3). Hence, the point lies in the III quadrant. (iii) The point is (-5,3). Hence, the point lies in the II quadrant. (iv) The point is (3,5). Hence, the point lies in the I quadrant. |
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65. |
Find the co-ordinates of points P, Q, R and S from given figure. |
Answer» Coordinate of P (5, 3) Coordinate of Q (-4, 6) Coordinate of R (-3, -2) Coordinate of S = (1, -5) |
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66. |
Out of the following, point lies to the right of the origin on X-axis.(A) (-2, 0) (B) (0, 2) (C) (2, 3) (D) (2, 0) |
Answer» Correct answer is (D) (2, 0) |
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67. |
Out of the following, point lies to the right of the origin on X-axis. (A) (-2,0) (B) (0,2) (C) (2,3) (D) (2,0) |
Answer» The correct answer is : (D) (2, 0) |
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68. |
The coordinates of the point P are (-3, 2). Find the coordinates of the point Q which lies on the line joining P and origin such that OP = OQ. |
Answer» Let the coordinates of Point Q are (x, y) and coordinates of origin O are (0, 0) Since OP = OQ Points are: P (-3, 2), Q(x, y) and O (0, 0) Q is the mid point 0 = \(\frac{-3 + x}2\) x = 3 0 = \(\frac{2 + y}2\) y = - 2 Therefore coordinates are (3, -2) |
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69. |
Are the positions of (5, -8) and (-8, 5) Is same ? Justify your answer. |
Answer» The positions of (5, -8) and (-8, 5) are not same. They are two distinct points. (5, -8) lies at a distance of 5 units from Y – axis and 8 units from X – axis on down side of the origin. So it lies in Q4 . Where as (- 8, 5) lies in Q2. The point is at a distance of 8 units from Y – axis on left side of the origin and 5 units from X – axis. |
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70. |
In which quadrant are the following points? i. whose both co-ordinates are positive. ii. whose both co-ordinates are negative. iii. whose x co-ordinate is positive and the y coordinate is negative.iv. whose x co-ordinate is negative and y co-ordinate is positive. |
Answer» i. Quadrant I ii. Quadrant III iii. Quadrant IV iv. Quadrant II |
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71. |
Write the abscissae and ordinates of the following points. i)(4,-8) ii)(-5,3) iii)(0,0)iv)(5, 0) v)(0, -8) Note: Plural of abscissa is abscissae. |
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72. |
Any point on the line y = x is of the form _____. (A) (a, a) (B) (0, a) (C) (a, 0) (D) (a, -a) |
Answer» Correct option is (A) (a, a) |
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73. |
What is the equation of the X-axis ?(A) x = 0(B) y = 0(C) x + y = 0(D) x = y |
Answer» Correct option is (B) y = 0 |
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74. |
Some points are shown in the adjoining figure. With the help of it answer the following questions :i. Write the co-ordinates of the points Q and R. ii. Write the co-ordinates of the points T and M. iii. Which point lies in the third quadrant ? iv. Which are the points whose x and y co-ordinates are equal ? |
Answer» i. Q(-2, 2) and R(4, -1) ii. T(0, -1) and M(3, 0) iii. Point S lies in the third quadrant. iv. The x and y co-ordinates of point O are equal. |
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75. |
In which quadrant does the point (-4, -3) lie? (A) First (B) Second (C) Third (D) Fourth |
Answer» (C) The answer is third |
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76. |
Which of the points P(-1, 1), Q(3, -4), R( -1, -1), S(-2, -3), T (-4, 4) lie in the fourth quadrant? (A) P and T (B) Q and R (C) only S (D) P and R |
Answer» (B) The answer is Q and R |
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77. |
If (x, y) is a point in fourth quadrant, that A) x > 0, y < 0 B) x > 0, y > 0 C) x < 0, y < 0D) x < 0, y > 0 |
Answer» Correct option is (A) x > 0, y < 0 If (x, y) lies in \(4^{th}\) quadrant. Then x > 0 & y < 0 A) x > 0, y < 0 |
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78. |
What is the nature of the line which includes the points (-5, 5), (6, 5), (-3, 5), (0, 5)?(A) Passes through the origin (B) Parallel to Y-axis (C) Parallel to X-axis (D) None of these |
Answer» The y co-ordinate of all the points is the same. ∴ The line which passes through the given points is parallel to X-axis. Correct option is (C) Parallel to X-axis |
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79. |
Which of the equations given below have graphs parallel to the X-axis, and which ones have graphs parallel to the Y-axis?i. x = 3 ii. y – 2 = 0iii. x + 6 = 0 iv. y = -5 |
Answer» i. The equation of a line parallel to the Y-axis is x = a. ∴ The line x = 3 is parallel to the Y-axis. ii. y – 2 = 0 ∴ y = 2 The equation of a line parallel to the X-axis is y = b. ∴ The line y – 2 = 0 is parallel to the X-axis. iii. x + 6 = 0 ∴ x = -6 The equation of a line parallel to the Y-axis is x = a. ∴ The line x + 6 = 0 is parallel to the Y-axis. iv. The equation of a line parallel to the X-axis is y = b. ∴ The line y = – 5 is parallel to the X-axis |
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80. |
What is the nature of the line which includes the points (-5, 5), (6, 5), (-3, 5), (0, 5)? (A) Passes through the origin (B) Parallel to Y-axis (C) Parallel to X-axis (D) None of these |
Answer» (C) Parallel to X-axis The y co-ordinate of all the points is the same. ∴ The line which passes through the given points is parallel to X-axis. |
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81. |
Are the points (5, 7) and (7, 5) equal ? |
Answer» No, the given points (5, 7) and (7, 5) are not equal. Why because, the above two points represent two different points in the coordinate plane. So they are not equal. For (x1, y1) = (x2, y1) then x1 must be equal to x2 and y1 must be equal to y2. So to become (5, 7) = (7, 5) 5 should be equal to 7, which is impossible. So (5, 7) will not be equal to (7, 5). |
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82. |
The points (–5, 2) and (2, – 5) lie in theA. same quadrantB. II and III quadrants, respectivelyC. II and IV quadrants, respectivelyD. IV and II quadrants, respectively |
Answer» C. on x – axis Explanation: (-5,2) is of the form (-x,y) so it lies in the II quadrant. (2,-5) is of the form (x,-y) so it lies in IV quadrant. (C) II and IV quadrants, respectively Hence, (C) is the correct option. |
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83. |
If the perpendicular distance of a point P from the x-axis is 5 units and the foot of the perpendicular lies on the negative direction of x-axis, then the point P hasA. x – coordinate = – 5B. y – coordinate = 5 onlyC. y – coordinate = – 5 onlyD. y – coordinate = 5 or –5 |
Answer» D. y – coordinate = 5 or –5 Explanation: Perpendicular distance from x-axis = Ordinate = 5 The negative direction of x-axis doesn’t decide the sign of the ordinate. (D) y-coordinate = 5 or -5. Hence, (D) is the correct option. |
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84. |
If the coordinates of the two points are P (–2, 3) and Q(–3, 5), then (abscissa of P) – (abscissa of Q) is (A) – 5 (B) 1 (C) – 1 (D) – 2 |
Answer» (b) 1 We have, points P(- 2, 3) and Q(- 3, 5) Here, abscissa of Pi.e., x-coordinate of Pis -2 and abscissa of Q i.e., x-coordinate of Q is -3. So, (Abscissa of P) – (Abscissa of Q) = – 2 – (-3) = -2 + 3 = 1. |
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85. |
The point (- 2, 0) lies on A) OX B) OX’ C) OY D) OY’ |
Answer» Correct option is (B) OX’ y-coordinate of point (-2, 0) is O. \(\therefore\) (- 2, 0) lies on negative x-axis. i.e., (- 2, 0) lies on OX'. Correct option is B) OX’ |
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86. |
A (2, 5) and B (3, 7) are points in a graph sheet. The ordinate of B is more than that of A by A) 1 B) 2 C) 3 D) 4 |
Answer» Correct option is (B) 2 Ordinate of point B(3, 7) = 7 Ordinate of point A(2, 5) = 5 \(\because\) 7 - 5 = 2 Hence, the ordinate of B is 2 more than the ordinate of A. Correct option is B) 2 |
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87. |
The point which lies on both the axes is A) (2,-3)B) (- 5, – 8) C) (0, 0) D) (- 1, 4) |
Answer» Correct option is (C) (0, 0) Both axes intersect each other at origin. \(\therefore\) Origin lies on both axes. Hence the point which lies on both axes is origin (0, 0). Correct option is C) (0, 0) |
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88. |
The point (0, – 3) lies on A) OX B) OX’ C) OY D) OY’ |
Answer» Correct option is (D) OY’ x-coordinate of point (0, -3) is O. \(\therefore\) (0, -3) lies on negative y-axis. i.e., (0, -3) lies on OY'. Correct option is D) OY’ |
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89. |
The ordinate of the point (4, – 6) is A) 2 B) – 2 C) – 6 D) 2 |
Answer» Correct option is (C) –6 The ordinate of the point (4, -6) = y-coordinate of point (4, -6) = - 6 Correct option is C) – 6 |
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90. |
Which of the following points abscissa is more than its ordinate by 2 ? A) (- 4, 2) B) (2, 4) C) (- 1, 1) D) (1,-1) |
Answer» Correct option is (D) (1,-1) (-4, 2); -4 < 2 \(\Rightarrow\) abscissa < ordinate (2, 4); 2 < 4 \(\Rightarrow\) abscissa < ordinate (-1, 1); -1 < 1 \(\Rightarrow\) abscissa < ordinate (1, -1); 1 > -1 and 1 - (-1) = 2 i.e., abscissa is more than its ordinate by 2. Correct option is D)(1,-1) |
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91. |
The point with abscissa 3 and whose ordinate is less than its abscissa by 4, isA) (3, 4)B) (-3, 4) C) (-1, 3) D) (3,-1) |
Answer» Correct option is (D) (3,-1) Abscissa = x-coordinate of point = 3 Ordinate = y-coordinate of point = abscissa - 4 = 3 - 4 = -1 \(\therefore\) Point is (x, y) = (3, -1). Correct option is D) (3,-1) |
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92. |
What is the equation of the X-axis? (A) x = 0 (B) y = 0 (C) x + y = 0 (D) x = y |
Answer» (B) The answer is y = 0 |
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93. |
Any point on the line y = x is of the form _____. (A) (a, a) (B) (0, a) (C) (a, 0)(D) (a, -a) |
Answer» (A) The answer is (a, a) |
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94. |
Y-axis and line x = – 4 are parallel lines. What is the distance between them? |
Answer» Equation of Y-axis is x = 0. Equation of the line parallel to the Y-axis is x = – 4. … [Given] ∴ Distance between the Y-axis and the line x = – 4 is 0 – (- 4) … [0 > -4] = 0 + 4 = 4 units ∴ The distance between the Y-axis and the line x = – 4 is 4 units. [Note: The question is modified as X-axis cannot be parallel to the line x = – 4.] |
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95. |
Find what the following equations become when the origin is shifted to the point (1, 1)? (i) x2 + xy – 3x – y + 2 = 0 (ii) x2 – y2 – 2x + 2y = 0 (iii) xy – x – y + 1 = 0 (iv) xy – y2 – x + y = 0 |
Answer» To find: Transformed equation of given equation when the origin (0, 0) is shifted at point (ab/(a – b), 0). We know that, when we transform origin from (0, 0) to an arbitrary point (p, q), the new coordinates for the point (x, y) becomes (x + p, y + q), and hence an equation with two variables x and y must be transformed accordingly replacing x with x + p, and y with y + q in original equation. Since, origin has been shifted from (0, 0) to (1, 1); therefore any arbitrary point (x, y) will also be converted as (x + 1, y + 1) or (x + 1, y + 1). (i) x2 + xy – 3x – y + 2 = 0 Substituting the value of x by x + 1 and y by y + 1, we have = (x + 1)2 + (x + 1)(y + 1) – 3(x + 1) – (y + 1) + 2 = 0 = x2 + 1 + 2x + xy + x + y + 1 – 3x – 3 - y - 1 + 2 = 0 = x2 + xy = 0 Hence, the transformed equation is x2 + xy = 0. (ii) x2 – y2 – 2x + 2y = 0 Substituting the value of x and y by x + 1 and y + 1 respectively, we have = (x + 1)2 – (y + 1)2 – 2(x + 1) + 2(y + 1) = 0 = x2 + 1 + 2x - y2 – 1 – 2y – 2x – 2 + 2y + 2 = 0 = x2 - y2 = 0 Hence, the transformed equation is x2 - y2 = 0. (iii) xy – x – y + 1 = 0 Substituting the value of x and y by x + 1 and y + 1 respectively, we have = (x + 1)(y + 1) – (x + 1) - (y + 1) + 1 = 0 = xy + x + y + 1 – x – 1 – y – 1 + 1 = 0 = xy = 0 Hence, the transformed equation is xy = 0. (iv) xy – y2 – x + y = 0 Substituting the value of x and y by x + 1 and y + 1 respectively, we have = (x + 1)(y + 1) – (y + 1)2 - (x + 1) + (y + 1) = 0 = xy + x + y + 1 – y2 – 1 – 2y - x – 1 + y + 1 = 0 = xy - y2 = 0 Hence, the transformed equation is xy - y2 = 0. |
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96. |
If (2, p) is the midpoint of the line segment joining the points A (6, -5) and B (-2, 11), find the value of p. |
Answer» Given: (2, p) is the mid point of the line segment joining the points A (6, -5), B (-2, 11) To find: the value of p p = (-5+11)/2 = 6/2 = 3 |
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97. |
At what point the origin be shifted so that the equation x2 + xy – 3x + 2 = 0 does not contain any first-degree term and constant term? |
Answer» Given: The equation x2 + xy – 3x + 2 = 0 We know that the origin has been shifted from (0, 0) to (p, q) So any arbitrary point (x, y) will also be converted as (x + p, y + q). The new equation is: (x + p)2 + (x + p)(y + q) – 3(x + p) + 2 = 0 Upon simplification, x2 + p2 + 2px + xy + py + qx + pq – 3x – 3p + 2 = 0 x2 + xy + x(2p + q – 3) + y(q – 1) + p2 + pq – 3p – q + 2 = 0 For no first degree term, we have 2p + q – 3 = 0 and p – 1 = 0, and For no constant term we have p2 + pq – 3p – q + 2 = 0. By solving these simultaneous equations we have p = 1 and q = 1 from first equation. The values p = 1 and q = 1 satisfies p2 + pq – 3p – q + 2 = 0. Hence, the point to which origin must be shifted is (p, q) = (1, 1). |
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98. |
Find what the following equations become when the origin is shifted to the point (1, 1)?(i) x2 + xy – 3x – y + 2 = 0(ii) x2 – y2 – 2x + 2y = 0(iii) xy – x – y + 1 = 0(iv) xy – y2 – x + y = 0 |
Answer» (i) x2 + xy – 3x – y + 2 = 0 Firstly let us substitute the value of x by x + 1 and y by y + 1 Then, (x + 1)2 + (x + 1) (y + 1) – 3(x + 1) – (y + 1) + 2 = 0 x2 + 1 + 2x + xy + x + y + 1 – 3x – 3 – y – 1 + 2 = 0 Upon simplification we get, x2 + xy = 0 ∴ The transformed equation is x2 + xy = 0. (ii) x2 – y2 – 2x + 2y = 0 Let us substitute the value of x by x + 1 and y by y + 1 Then, (x + 1)2 – (y + 1)2 – 2(x + 1) + 2(y + 1) = 0 x2 + 1 + 2x – y2 – 1 – 2y – 2x – 2 + 2y + 2 = 0 Upon simplification we get, x2 – y2 = 0 ∴ The transformed equation is x2 – y2 = 0. (iii) xy – x – y + 1 = 0 Let us substitute the value of x by x + 1 and y by y + 1 Then, (x + 1) (y + 1) – (x + 1) – (y + 1) + 1 = 0 xy + x + y + 1 – x – 1 – y – 1 + 1 = 0 Upon simplification we get, xy = 0 ∴ The transformed equation is xy = 0. (iv) xy – y2 – x + y = 0 Let us substitute the value of x by x + 1 and y by y + 1 Then, (x + 1) (y + 1) – (y + 1)2 – (x + 1) + (y + 1) = 0 xy + x + y + 1 – y2 – 1 – 2y – x – 1 + y + 1 = 0 Upon simplification we get, xy – y2 = 0 ∴ The transformed equation is xy – y2 = 0. |
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99. |
At what point the origin be shifted so that the equation x2 + xy – 3x + 2 = 0 does not contain any first-degree term and constant term? |
Answer» Given, equation x2 + xy – 3x + 2 = 0 Let’s assume that the origin is shifted at point (p, q). To find: The shifted point (p, q) satisfying the question’s conditions. We know that, when we transform origin from (0, 0) to an arbitrary point (p, q), the new coordinates for the point (x, y) becomes (x + p, y + q), and hence an equation with two variables x and y must be transformed accordingly replacing x with x + p, and y with y + q in original equation. Since, origin has been shifted from (0, 0) to (p, q); therefore any arbitrary point (x, y) will also be converted as (x + p, y + q). The New equation hence becomes: = (x + p)2 + (x + p)(y + q) – 3(x + p) + 2 = 0 = x2 + p2 + 2px + xy + py + qx + pq – 3x – 3p + 2 = 0 = x2 + xy + x(2p + q – 3) + y(q – 1) + p2 + pq – 3p – q + 2 = 0 For no first degree term, we have 2p + q - 3 = 0 and p – 1 = 0, and for no constant term we have p2 + pq – 3p - q + 2 = 0. Solving these simultaneous equations we have p = 1 and q = 1 from first equation. And, p = 1 and q = 1 satisfies p2 + pq – 3p - q + 2 = 0. Hence, the point to which origin must be shifted is (p, q) = (1, 1). |
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100. |
A straight line is parallel to the lines 3x – y – 3 = 0 and 3x – y + 5 = 0 and lies between them. Find its equation if its distances from these lines are in the ratio 3 : 5. (a) 3x – y + 10 = 0 (b) 3x – y = 0 (c) 3x – y = 0 (d) 3y – x – 10 = 0 |
Answer» (b) 3x – y = 0 Given lines are 3x – y – 3 = 0 and 3x – y + 5 = 0. Line parallel to the given lines can be written as 3x – y + c = 0 ...(i) Let us taken a point, say, (0, c) on (i) (Putting x = 0 in (i), we get y = c) ∴ \(\frac{\text{Distance of (0,c) from}\,3x-y-3}{\text{Distance of (0,c) from}\,3x-y+5}\) = \(\frac{3}{5}\) ⇒ \(\frac{\frac{|3\times0-c-3|}{\sqrt{3^2+1^2}}}{\frac{|3\times0-c+5|}{\sqrt{3^2+1^2}}}\) = \(\frac{3}{5}\)⇒ \(\frac{c+3}{-c+5}\) = \(\frac{3}{5}\) ⇒ 5c + 15 = – 3c + 15 ⇒ 8c = 0 ⇒ c = 0. Substituting c = 0 in (i), the required equation is 3x – y = 0. |
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