Question

Which of these points are on a line that has a slope of -3?

Answer 1

Simple....

using the formula $\frac{ y_{1}- y_{2} }{ x_{1}- x_{2} }$ to find slope....

1.)  (9,2)(4,3)

$\frac{2-3}{9-4}= -\frac{1}{5}$ (No)

2.)  (9,2)(3,4)

$\frac{2-4}{9-3} = -\frac{2}{6} =- \frac{1}{3}$ (No)

3.)  (2,9)(3,4)

$\frac{9-4}{2-3} = \frac{5}{-1} =-5$ (No)

4.)  (2,9)(4,3)

$\frac{9-3}{2-4} = \frac{6}{-2} =-3$ (YES!)

Thus, your answer.