## Precalculus (6th Edition) Blitzer

$a \approx 18$ cm
RECALL: (1) $\sin{\theta} = \dfrac{\text{opposite side}}{\text{hypotenuse}}$ (2) $\cos{\theta} = \dfrac{\text{adjacent side}}{\text{hypotenuse}}$ (3) $\tan{\theta} = \dfrac{\text{opposite side}}{\text{adjacent side}}$ Use (3) above to obtain: $\tan{61^o}=\dfrac{a}{10} \\a=10(\tan{61^o})$ Use a calculator in DEG mode to obtain $\\a=18.04047755 \\a \approx 18$ cm