Answer:
First option sin20 times eight
Explanation:
This is a right triangle, and we have the hypotenuse 8 (the side opposite to the angle of 90°), and angle of 20°, and we want to calculate the opposite leg (x) to the angle of 90°. The trigonometric function that relates the opposite leg to an angle and the hypotenuse is sine:
![sin 20^(\°)=(Opposite leg)/(Hypotenuse)](https://img.qammunity.org/2020/formulas/mathematics/middle-school/929sewp0l6o7q3pygyb6xi2gqxi1dhqs30.png)
Replacing the values:
![sin 20^(\°)=(x)/(8)](https://img.qammunity.org/2020/formulas/mathematics/middle-school/rcwzuifu4sb7sux0onafqlhig115t2vfsc.png)
Solving for x: Multiplying both sides of the equation by 8:
![sin20^(\°).8=(x)/(8).8\\ sin20^(\°).8=x\\x=sin20^(\°).8](https://img.qammunity.org/2020/formulas/mathematics/middle-school/bdt0f99zckkx0hchvpl319kn4fshao5j23.png)
Answer: We can calculate x with sin20 times eight