Question

Find the length of the side labled x

Answer 1

now, the picture looks a bit misleading, the angle on the bottom-right corner doesn't look at all like a 20° angle, so let me assume the 20° angle is the angle up above, like you see in the picture below, because that looks like a 20° one, and the number there, is not very clear which one is pointing to.

`\cos(64^o )=\cfrac{\stackrel{adjacent}{h}}{\underset{hypotenuse}{18}}\implies 18\cos(64^o)=h \\\\[-0.35em] ~\dotfill\\\\ \cos(20^o )=\cfrac{\stackrel{adjacent}{h}}{\underset{hypotenuse}{x}}\implies x=\cfrac{h}{\cos(20^o )}\implies x=\cfrac{18\cos(64^o)}{\cos(20^o )}\implies x\approx 8.4`

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