What is the distance between the walls?

Question

A source of laser light sends rays AB and AC toward two opposite walls of a hall. The light rays strike the walls at points B and C, as shown below:

What is the distance between the walls? (1 point)

		110.90 m
		149.28 m
		103.92 m
		173.20 m

Answer 1

Distance between walls=left side of floor + right side of floor

Wall/floor=tan of angle because the angle, floor, and wall are part of a 90 degree triangle.

60/left sideof floor=tan(60)

40/right side of floor=tan(30)

Left side of floor=60÷tan(60) or 34.64

Right side of floor=40/tan(30) or 69.28

Distance between walls =34.64 + 69.28 or 103.92