

InterviewSolution
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Find the equation of a line perpendicular to the line 4x + 2y - 11 = 0 and passes through a point (3, 4)1. 2x + y - 10 = 02. 2x - y - 2 = 03. 2y - x - 5 = 04. 2y + x - 11 = 0 |
Answer» Correct Answer - Option 3 : 2y - x - 5 = 0 Concept: The general equation of a line is y = mx + c where m is the slope and c is any constant
Equation of a line with slope m and passing through (x1, y1) (y - y1) = m (x - x1) Equation of a line passing through (x1, y1) and (x2, y2) is: \(\rm {y-y_1\over x-x_1}={y_2-y_1\over x_2-x_1}\) Calculation: Given line 4x + 2y - 11 = 0 ⇒ y = -2x + 5.5 ⇒ Slope(m1) = -2 and c1 = 5.5 Now for the slope of perpendicular line (m2) m1 × m2 = -1 ⇒ -2 × m2 = -1 ⇒ m2 = \(1\over2\) Perpendicular line has the slope \(1\over2\) and passes through (3, 4) ∴ Equation of the perpendicular line is (y - y1) = m (x - x1) ⇒ y - 4 = \(1\over2\) (x - 3) ⇒ 2y - x - 5 = 0 |
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