which expression finds the measure of an angle that is coterminal with a 300° angle?\n300° - 860°\n300°…

Answer:

D. $300^{\circ}-720^{\circ}$

Explanation:

Step1: Recall coterminal - angle formula

Coterminal angles of an angle $\theta$ are given by $\theta\pm n\times360^{\circ}$, where $n$ is an integer.

Step2: Analyze each option

Option A:

$300^{\circ}-860^{\circ}=300^{\circ}-(2\times360^{\circ}+140^{\circ})=- 560^{\circ}$, not in the form $\theta\pm n\times360^{\circ}$.

Option B:

$300^{\circ}-840^{\circ}=300^{\circ}-(2\times360^{\circ}+120^{\circ})=-540^{\circ}$, not in the form $\theta\pm n\times360^{\circ}$.

Option C:

$300^{\circ}-740^{\circ}=300^{\circ}-(2\times360^{\circ}+20^{\circ})=-440^{\circ}$, not in the form $\theta\pm n\times360^{\circ}$.

Option D:

$300^{\circ}-720^{\circ}=300^{\circ}-2\times360^{\circ}$, which is in the form $\theta - n\times360^{\circ}$ with $n = 2$. So this angle is coterminal with $300^{\circ}$.