Answer is in the photo. I couldn't attach it here, but uploaded it to a file hosting. link below! Good Luck!
cutt.ly/wzUiVyK
answer: it is d
step-by-step explanation:
yx = 36
cos f = opposite side/ hypotenuse
cos f = yw / yx
we know cos f = 4/9 and yw =16
4/9 = 16/yx
multiply each side by yx
4/9 yx = 16/ yx * yx
4/9 yx = 16
multiply each side by 9/4
9/4 * 4/9 yx = 16 *9/4