Question

A streetlight post needs some extra support for potential bad weather and high winds. The city wants to install metal support brackets on the light post. Each bracket will be braced into the ground and will then attach to a point on the pole that is 4.5 ft. from the ground. Each bracket is 6.5 ft. long. How far from the base of the pole should each bracket be braced in the ground? Round to the nearest tenth.(1 point)

62.5 ft.

7.9 ft.

4.7 ft.

22.0 ft.

Answer 1

Use the Pythagorean theorem. Let x be the horizontal distance from the pole:
x^2 + 4.5^2 = 6.5^2 ⇒ x = sqrt(6.5^2 − 4.5^2) = sqrt(42.25 − 20.25) = sqrt(22) ≈ 4.7 ft.

Answer: 4.7 ft.