Answer
Chapter 2 - Section 2.3 Problem Set: 30 (Answer)
Refer to Figure I
$\angle A$ = $69^{\circ}$
$a = 3.9$ ft (To two significant digits)
$b = 1.5$ ft (To two significant digits)
Work Step by Step
Chapter 2 - Section 2.3 Problem Set: 30 (Solution)
Refer to Figure I
$\angle A$ + $\angle B$ + $90^{\circ}$ = $180^{\circ}$ ($\angle$ sum of $\triangle$)
$\angle A$ + $21^{\circ}$ + $90^{\circ}$ = $180^{\circ}$
$\angle A$ = $69^{\circ}$
$\cos 21^{\circ} = \frac{a}{c}$
$a = 4.2 \cdot \cos 21^{\circ}$
$a = 3.9$ ft (To two significant digits)
$\sin 21^{\circ} = \frac{b}{c}$
$b = 4.2 \cdot \sin 21^{\circ}$
$b = 1.5$ ft (To two significant digits)
