InterviewSolution
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The equation of the straight line passing through the point (3, 2) and perpendicular to the line y = x isA. x – y = 5B. x + y = 5C. x + y = 1D. x – y = 1 |
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Answer» B. x + y = 5 Explanation: Given that straight line passing through the point (3, 2) And perpendicular to the line y = x Let the equation of line ‘L’ is y – y1 = m(x – x1) Since, L is passing through the point (3, 2) ∴ y – 2 = m(x – 3) … (i) Now, given eq. is y = x Since, the above equation is in y = mx + b form So, the slope of this equation is 1 It is also given that line L and y = x are perpendicular to each other. We know that, when two lines are perpendicular, then m1 × m2 = -1 ∴ m × 1 = -1 ⇒ m = -1 Putting the value of m in equation (i), we get y – 2 = (-1) (x – 3) ⇒ y – 2 = -x + 3 ⇒ x + y = 3 + 2 ⇒ x + y = 5 Hence, the correct option is (b) |
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