Question

Prove (by vectors) that the points $(-3,5),(-2,3)$ and $(4,-9)$ are collinear.

Answer 1

Prove that the point $(-3,5),(-2,3)$ & $(4,-9)$

are collinear

if three pls $(-3,5),(-2,3)$ & $(4,-9)$ are co;;inear than the measured slope will be equal

Slope of $(-3,5)$ & $(-2,3)=\frac{y_2-y_1}{x_2-x_1}$

$=\frac{3-5}{-2-(-3)}=\frac{-2}{1}=2$

Slope of $(-3,5)$ & $(4,-9)=\frac{-9-5}{4-(-3)}=\frac{-14}{7}=-2$

Hence slope are equal, pts are collinear