Question

Another wooden plank is leaning against an outside wall of a building. The bottom of the plank is 9 ft from the wall. The length of the plank is 41 ft. Find each of the following values, and show all your work. (a) Find the value of x. Round to the nearest tenth of a degree.
(b) Find the height above the ground where the plank touches the wall. Round to the nearest foot.        sorry the link for the triangle isn't working

Answer 1

Given:
bottom of the plank or ground is 9 feet from the wall
length of the plant is 41 ft
height of the wall is unknown.

Let us use the Pythagorean theorem.

a² + b² = c²
a² + (9ft)² = (41ft)²
a² + 81 ft² = 1,681 ft²
a² = 1,681 ft² - 81 ft²
a² = 1,600 ft²
√a² = √1,600 ft²
a = 40 ft

The height of the wall is 40 ft.