# If A = 40°, B = 60°, and a = 20, find b.

If $$A = 40^{\circ}, B = 60^{\circ}$$, and $$a = 20$$, find b.

• Questions are typically answered in as fast as 30 minutes

### Plainmath recommends

• Get a detailed answer even on the hardest topics.
• Ask an expert for a step-by-step guidance to learn to do it yourself.

Pohanginah

Use the Law of Sinse: $$\displaystyle\frac{{\sin{{A}}}}{{a}}=\frac{{\sin{{B}}}}{{b}}$$
Substitute given $$A=40^{\circ}, B=60^{\circ}$$, and $$a=20$$, then find b

$$\frac{\sin40^{\circ}}{20}=\frac{\sin60^{\circ}}{b}$$

$$b=\frac{20\sin60^{\circ}}{\sin40^{\circ}}$$

$$b \sim 26.9$$