Answer
$A = 141.8˚$
$b \approx 118$ cm
$c \approx 214$ cm
Work Step by Step
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
