Question

What two sides do you need to find the cosine of angle B?

Answer 1

`cosB=(a)/(c)`

Explanation:

The cosine ratio is
`cosineX=(adjacent)/(hypotenuse)` for the given angle. In this case, the angle is B. So you need the side adjacent the angle B (next to) that is NOT the hypotenuse. You also need the hypotenuse. S you would need :

`cosB=(a)/(c)`

You can remember the ratios by using SOH-CAH-TOA.

Sine=Opposite/hypotenuse

Cosine=adjacent/hypotenuse

Tangent=opposite/adjacent