Triangles ABC and DEF are similar. Find the perimeter of triangle DEF. Round your answer to the nearest tenth.

Question

ab=4ft
bc=6ft
ac=5ft

de=6ft
ef= 9ft

there is no feet given for df

Please can anyone help me solve this with steps I don't understand how to do this. Thanking you in advance for any assistance.

Answer 1

Similar triangles have similar ratios

DE / AB = 6/4 = 3/2

EF/BC = 9/6 = 3/2

So we know that DF / AC = 3/2

We are given that AC = 5

So, DF / 5 = 3/2

We cross multiply to get 15 = DF x 2

So, DF = 15/2

And, to the nearest tenth it is equal to

7.5

Answer 2

(Meaning 7.5 was the answer sorry if I was unclear)