Question

A 15-foot flagpole leans slightly, such that it makes an 80° angle with the ground. The shadow of the flagpole is 10 feet long when the sun has an unknown angle of elevation. How could the angle of elevation of the sun, x, be determined?

Answer 1

Answer:   48°

Step-by-step explanation:

The shadow is the adjacent side and the length of the flag is the hypotenuse

$cos\ \theta=\dfrac{adjacent}{hypotenuse}\\\\\\cos\ \theta=\dfrac{10}{15}\\\\\\cos^{-1}(cos\ \theta)=cos^{-1}\bigg(\dfrac{10}{15}\bigg)\\\\\\.\qquad \qquad \boxed{\theta=48^o}$