Question

how do I find the correct answer? ( the top says "Triangles ABC and DEF are right triangles, as shown, ABC is similar DEF.)

Answer 1

The cosine relation is defined by the length of the adjacent side over the length of the hypotenuse.

So, for triangle ABC, the cosine of B is defined as:

`\cos (B)=(BC)/(AB)`

And for triangle DEF, since the triangles are similar, the cosine of B is equal the cosine of its corresponding angle E:

`\cos (E)=(EF)/(DE)`

So the correct options are the first and fifth ones.