Question

1) Which of the following pairs of equations are perpendicular to one another? a. 6x - 3y = 9 b. y = x + 1 y = 2x + 4 3y = 4x + 15 c. y = x - 4 d. y = x - 3 7x + 7y = 14 y = x + 8

Answer 1

d)

Explanation:

`7x+7y=14 => 7y=-7x+14 => y=-x+2`

Compare `y=-x+2`
with `y=x+8` when you multiply the coefficients of `x` together `-1 xx 1 = -1` this means they are perpendicular.