Mathematics for IGCSE & O level - Coordinate Geometry (Section 4 - No. 17)
Which of the following statements is true regarding the line perpendicular to y = (1/3)x + 2?
The gradient is 1/3
The gradient is -3
The y intercept is 2
The y intercept is 1/3
Explicació
Perpendicular lines have negative reciprocal gradients. The negative reciprocal of 1/3 is -3.