What is the measure of ∠R?
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Answer:
∠ R ≈ 36.9
Step-by-step explanation:
Using the cosine ratio in the right triangle
cosR = [tex]\frac{adjacent}{hypotenuse}[/tex] = [tex]\frac{RT}{RS}[/tex] = [tex]\frac{8}{10}[/tex] , then
∠ R = [tex]cos^{-1}[/tex] ([tex]\frac{8}{10}[/tex] ) ≈ 36.9 (to 1 dec. place )