Question

clue #6
use the given triangle to fill in the blank.
______b = $\frac{a}{c}$
a sin
b cos
c tan
d sec

Explanation:

Step1: Identify sides for angle B

For $\angle B$, opposite side = $b$, adjacent side = $a$, hypotenuse = $c$.

Step2: Match ratio to trig function

We need $\frac{a}{c}$: this is $\frac{\text{adjacent}}{\text{hypotenuse}}$, which is the cosine function.

Answer:

B. cos