Question

Really need help...

A 20 foot ladder touches a building 16 feet up the wall. What is the measure of the angle the Ladder makes with the Ground?

Which expression has a value of 1?
A. sinx+cosx
B. sin2x-cos2x
C. sin2x+cos2c
D. (sinx+cosx)2

Answer 1

sinθ = 16/20 = 0.8 
θ = arcsin(0.8) ≅ 53° 
::::: 
Use ^2 to represent ². 
Pythagorean identity: 
sin²(x) + cos²(x) = 1