Question

Solve for x. Round to the nearest tenth, If necessary.

Answer 1

Check the picture below.

`\cos(72^o )=\cfrac{\stackrel{adjacent}{3.9}}{\underset{hypotenuse}{x}} \implies x\cos(72^o)=3.9\implies x=\cfrac{3.9}{\cos(72^o)}\implies x\approx 12.6`

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