### Home > A2C > Chapter 3 > Lesson 3.1.1 > Problem 3-21

3-21.

Find the length of the side labeled in each triangle below.

Look at the angle measures. Does this type of triangle look familiar?

If you cannot solve it that way, refer to problem 1-61 or the Math Notes box in Lesson 1.2.1.

Look at the values given. Is it necessary to use the trigonometric identities, or is there an easier way?

Use the Pythagorean Theorem.