Question

CHECK MY WORK: Triangle ABC is similar to triangle DEF. Using the image below, prove that lines BC and EF have the same slope

Answer 1

Slope = rise/run
BA= 3
AC=3
slope of BC= -1
ED=2
DF=2
Slope of EF=-1

The slopes are equal therefore proving that the triangles are similar.

Answer 2

@Hero

Answer 3

You have to use similar triangles to prove that BC // EF --> they have the same slope

Answer 4

So, my answer isn't sufficient ?

Answer 5

Even it is correct, but you didn't use the given information (the triangles are similar), hence it is not valid

Answer 6

You need do:
1) AC// DF
2)AB//DE
3) the triangles are similar
--> BC // EF --> same slope

Answer 7

how do I prove that ac//df ?

Answer 8

slope of AC = 0
slope of DF =0

Answer 9

But I think it is + 3) --> BC // EF
no need to prove 2)

Answer 10

B= (4,-2) C= (1,1)

slope of BC = (4-1) / (-2 -1) =
3/-3 = -1

E= (4,4) F=(6,2)
slope of EF= (4-6) / (4-2) =
-2/2 = -1
The slopes are equal