Question

HELP PLEASE!!!! Triangle ABC is similar to triangle DEF. Using the image below, prove that parallel lines have the same slope. You must show all of your work to receive credit.

Answer 1

Take the coordinates of the endpoints of two corresponding lines. Let's use line BA and line ED. The coordinates are (-2, 5) and (-2, 1) for BA and (4, 4) and (4, 2) for ED. Now we need to apply the slope formula to prove that this pair of parallel lines has the same slope.
\[m =\frac{ y_2 - y_1 }{ x_2 - x_1 }\]
Do you got it from here? :)

Answer 2

My bad, vertical lines have an undefined slope, so you might wanna use the hypotenuse or horizontal lines, instead. :)