Question

Can someone help and explain

Answer 1

Answer:

∠ A ≈ 43.1°

Step-by-step explanation:

Using the Sine rule in Δ ABC , that is

$\frac{a}{sinA}$ = $\frac{c}{sinC}$ , substitute values

$\frac{20}{sinA}$ = $\frac{29}{sin82}$ ( cross- multiply )

29 × sinA = 20 × sin82 ( divide both sides by 29 )

sinA = $\frac{20sin82}{29}$ , thus

∠ A = $sin^{-1}$ ($\frac{20sin82}{29}$ ) ≈ 43.1° ( to 1 dec. place )