A surveyor is standing 115 feet from the base of the Washington Monument. The sureyor measures the angle of elevation to the top of the monument as 78.3. How tall is the Washington Monument?

Question

A surveyor is standing 115 feet from the base of the Washington Monument.  The sureyor measures the angle of elevation to the top of the monument as 78.3.  How tall is the Washington Monument?

The answer's 555 feet, but I'm not sure how to get it.  Can you explain?

Reiny · Answer

tan 78.3 = h/115 h = 115tan78.3 =555.3