Question

The measure of angle A to the nearest tenth of a degree is: A 18.5 B 19.5 C 20.5

Answer 1

The correct answer is 19.5

Explanation:

Answer 2

B

Explanation:

This is a right triangle as shown by the right angle.

• The side opposite the right angle is the hypotenuse, which is 9.
• The side opposite angle A is 3.

So we have the opposite of A and the hypotenuse.

The trigonometric ratio that relates opposite side to hypotenuse is SINE.

`sin\theta=(opposite)/(hypotenuse)`

Since, we need angle A,
`\theta` is A, opposite side is 3, and hypotenuse is 9, we substitute:

`sinA=(3)/(9)\\sinA=(1)/(3)`

To solve for the angle, we use our calculator and find the inverse sin of
`(1)/(3)` :

`A=sin^(-1)((1)/(3))\\A=19.47`

Rounding to nearest tenth of a degree:

`A=19.5`

B is the right choice.