## Trigonometry 7th Edition

$A = 141.8˚$ $b \approx 118$ cm $c \approx 214$ cm
1. Find the missing angle $A$ $A + 13.4 + 24.8 = 180$ $A + 38.2 = 180$ $A = 141.8˚$ 2. Find the unknown length $b$ $\frac{b}{sin(13.4)} = \frac{315}{sin(141.8)}$ $b = \frac{315sin(13.4)}{sin(141.8)}$ by GDC / calculator $b = \frac{73.00....}{0.618...}$ $b = 118.045...$ cm $b \approx 118$ cm 3. Find the unknown length $c$ $\frac{c}{sin(24.8)} = \frac{315}{sin(141.8)}$ $c = \frac{315sin(24.8)}{sin(141.8)}$ by GDC / calculator $c = \frac{132.127....}{0.618...}$ $c = 213.65...$ cm $c \approx 214$ cm