Question

Katrina said that the lines y=-2/3x + 5 and y = -3/2x + 2 are perpendicular. Explain Katrina's error.

Answer 1

There shouldn't be a negative in front of one of the equations.

Answer 2

Answer:

product of gradients of the two lines = 1 does not imply the lines being perpendicular, the product of gradients have to instead be equal to -1.