Question

Please help me on this

Answer 1

Answer: Option B.

Step-by-step explanation:

You neeed to use the trigonometric identity:

$sin\alpha=\frac{opposite}{hypotenuse}$

As you need to find sin∠A, you can identify in the right triangle that:

$opposite=8\\hypotenuse=10\\\alpha=A$

 Finally, substitute the angle, the lenght of the opposite side and the lenght of the hypotenuse into $sin\alpha=\frac{opposite}{hypotenuse}$ to find sin∠A. Then, you get:

$sinA=\frac{8}{10}$

Reducing the fraction:

$sinA=\frac{4}{5}$

This is the option B.