Answer
$α \approx 37^{\circ}$
$β \approx 53^{\circ}$
Work Step by Step
1. Find $ α$
$tan = \frac{opposite}{adjacent}$
$tan(α) = \frac{3}{4}$
by GDC / calculator
$α = 36.86989...^{\circ}$
$α \approx 37^{\circ}$
2. Find $β$
$tan = \frac{opposite}{adjacent}$
$tan(β) = \frac{4}{3}$
by GDC / calculator
$β = 53.1301...$
$β \approx 53^{\circ}$