Divide using synthetic division -3 1 8 9 -18

4/7

Step-by-step explanation:

Original equation, in general form: -7x - 4y - 6

Rearrange to get: 4y = -7x - 6

Divide both sides by 4 to get: y = -7/4(x) - 1.5

To find the slope of a line perpendicular to another line, take the original gradient, and find the negative inverse

So for here,

Original gradient: -7/4

Negative: 7/4

Negative Inverse: 4/7 (which is our gradient)

Done!