In △ABC, m∠A=15°, a=9, and b=12. Find c to the nearest tenth.

=20.0

Step-by-step explanation:

We can first find the value of the angle at B using the sine formula.

a/sine A=b/Sin B

9/sin 15=12/sin B

Sin B = (12 sin 15) / 9

Sin B=0.345

B=20.18°

Therefore angle C = 180 - (15+20.18)

=144.82°

a/Sin A=c/Sin C

9/Sin 15=c/Sin 144.82

c = (9 sin 144.82) / sin15

=20.0