Question

What is the measure of angle A in the triangle below?

us
B
18
9
A
A
С
30°
o 45°
60°
90°

Answer 1

To find the measure of Angle A, we'll need to use a trigonometric function.

Remember: SOH-CAH-TOA

Looking from Angle A, we know the opposite side and the hypotenuse. Therefore, we should use the sine function.

sin(A) = 9 / 18

---To solve for A, you'll need to use the inverse sin function on your calculator. It should look like so: sin^-1()

The inverse sin of 1/2 = 30

Answer: first option, 30 degrees

Hope this helps!