Question

use the image below.
find a.
(1 point)
10
5
$5\sqrt{2}$
$5\sqrt{3}$

Explanation:

Step1: Identify adjacent side to 60°

The side length 5 is adjacent to the 60° angle, and $a$ is the hypotenuse.

Step2: Use cosine definition

Cosine of an angle = $\frac{\text{adjacent}}{\text{hypotenuse}}$, so $\cos(60^\circ) = \frac{5}{a}$.
We know $\cos(60^\circ) = \frac{1}{2}$, so substitute:
$\frac{1}{2} = \frac{5}{a}$

Step3: Solve for $a$

Rearrange to isolate $a$: $a = 5 \times 2$

Answer:

10