Question

question 5 1 pts which trig function would be used to solve for x? cosine tangent pythagorean theorem sine

Explanation:

In a right - triangle, we have three main trigonometric functions: sine ($\sin\theta=\frac{\text{opposite}}{\text{hypotenuse}}$), cosine ($\cos\theta = \frac{\text{adjacent}}{\text{hypotenuse}}$) and tangent ($\tan\theta=\frac{\text{opposite}}{\text{adjacent}}$). The Pythagorean Theorem ($a^{2}+b^{2}=c^{2}$) is not a trigonometric function.

In the given right - triangle, the hypotenuse is 8, the angle is $72^{\circ}$, and the side $x$ is adjacent to the $72^{\circ}$ angle. The cosine function relates the adjacent side and the hypotenuse. So we use the cosine function.

Answer:

A. Cosine