Question

what is the value of the x-coordinate of point a? choose 1 answer: a sin(20°) b cos(20°) c sin(110°) d cos(110°) e sin(200°) f cos(200°)

Explanation:

Step1: Find angle of point A

Point A is 20° left of positive y-axis, so angle from positive x-axis is 90°+20°=110°.

Step2: Use unit circle x-coordinate rule

x-coordinate = cos(angle). So x = cos(110°).

Answer:

D. cos(110°)