Question

In ΔWXY, the measure of ∠Y=90°, YX = 40, XW = 41, and WY = 9. What ratio represents the cosine of ∠W?

Answer 1

`cos(W) = (9)/(41)`

Explanation:

Cosine of an angle:

The cosine of an angle, in a right triangle, is the length of the side adjacent to this angle divided by the hypotenuse.

Length of the largest side:

The length of the largest side is 41, that is, the hypotenuse is 41. The hypotenuse is XW.

WY = 9.

This means that the length of the adjacent side to angle W is 9.

What ratio represents the cosine of ∠W?

Adjacent side has length 9, hypotenuse has length 41. So

`cos(W) = (9)/(41)`