Question

The diagonal in a rectangle is 20 units long, and the angle between the diagonal and a side is 36º 42'.

What is the length of the side adjacent to the given angle? Round off your answer to four significant digits.
A. 11.95
B. 14.91
C. 24.94
D. 16.04

Answer 1

Side adjacent to the given angle: x
Diagonal=hypotenuse=20
cos (36° 42') =(side adjacent to angle 36° 42')/Hypotenuse
cos (36° 42')=x/20
Solving for x. Multiplying both sides of the equation by 20:
20 cos (36° 42')=20 (x/20)
20 cos (36° 42')=x
x=20 cos (36° 42')
x=20 (0.801775644)
x=16.03551288
x=16.04

Answer: Option D. 16.04