Question

A 15-foot ladder leans against a wall at a 60 degree angle of elevation. What is the distance from the ladder's base to the wall?

Answer 1

Cos60= x/15

x=15cos60
x=15/2 or 7.5

Answer 2

A picture is usually a good place to start:

Answer 3

Naturally, we have to assume that the angle between ground and wall is a right angle.

After that, remembering that the \(\cos\) function is the fraction \(\large\frac{\text{adjacent}}{\text{hypotenuse}}\) leads to the result @MelissaVictoria4002 gave you.