Question

the equation sin(40°) = b/20 can be used to determine the length of line segment ac. what is the length of ac? round to the nearest tenth.

Explanation:

Step1: Given the sine - value equation

We are given $\sin(40^{\circ})=\frac{b}{20}$, where $b$ is the length of $\overline{AC}$.

Step2: Solve for $b$

Multiply both sides of the equation by 20: $b = 20\times\sin(40^{\circ})$.
We know that $\sin(40^{\circ})\approx0.6428$.
So, $b=20\times0.6428 = 12.856\approx12.9$.

Answer:

$12.9$ cm