### Home > PC > Chapter 1 > Lesson 1.2.1 > Problem1-74

1-74.

Solve $ΔPQR$ at right.

First label the triangle with lower case letters for the sides.

What does it mean to solve a triangle?

Make a chart. Fill in with known information. Then find the unknown values.

Find the lengths of all $3$ sides and the $3$ angle measurements.

 Side Angle $\color{red}{q=16 \text{ cm}}$ $\color{red}{Q=90^{\large \circ} }$ $\color{red}{p=8 \text{ cm}}$ $P=?$ $r=?$ $R=?$

How could you find Angle P?

Once you have two angles in the right triangle, how do you find the 3rd angle?

In a right triangle, what famous theorem helps in finding a third side if two sides are already known?

Use the Sine function or the Law of Sines.

$180°$ (the sum of the first two angles)

Pythagorean Theorem
$a² + b² = c²$