Question

question 20 (1 point)
what is the measure of ∠b in the triangle shown?

a) 45°
b) 60°
c) 90°
d) 30°

Explanation:

Step1: Recall trigonometric ratio

We use the cosine ratio: $\cos B=\frac{\text{adjacent}}{\text{hypotenuse}}$.

Step2: Identify sides

Adjacent side to angle $B$ is $\sqrt{3}$, hypotenuse is $2$. So $\cos B = \frac{\sqrt{3}}{2}$.

Step3: Find angle

We know that $\cos 30^{\circ}=\frac{\sqrt{3}}{2}$.

Answer:

d) $30^{\circ}$