How do you use the sum and difference formulas to evaluate angles not on the unit circle? How do you use the sum and difference formulas verify identities?

I uploaded the answer to a file hosting. Here's link:

cutt.ly/nz6VGda

the answer is 0.071

good luck! : d

answer:  

step-by-step explanation:

here x represents the height of the pole,

and, the height of the shadow of the pole is 12 feet.

also, the angle of elevation from the top of the pole is 40°,

therefore,

by the low of sine,

which is the required equation for finding the value of x,