A beam rests against a wall, forming a 65° with the floor. Use the function y = 9 sec e to find the length of the beam to

the nearest tenth of a foot.

(1 point)

8.2 ft

21.3 ft

9.9 ft

18.7 ft

1 answer

To find the length of the beam, we need to set up a right triangle with the beam as the hypotenuse. The angle between the beam and the floor is 65°, so the angle between the beam and the wall is 90° - 65° = 25°.

Let the length of the beam be x. Then, using trigonometry, we have:

sec(25°) = hypotenuse/adjacent
sec(25°) = x/y
y = x/cos(25°)

We are given that y = 9. Therefore:
9 = x/cos(25°)
x = 9cos(25°)

Using a calculator to find cos(25°) ≈ 0.9063 and multiplying by 9, we get:
x ≈ 9(0.9063) ≈ 8.2 ft

Therefore, the length of the beam is approximately 8.2 ft to the nearest tenth of a foot. The answer is 8.2 ft.