### Home > GC > Chapter 4 > Lesson 4.1.1 > Problem 4-8

4-8.

in the diagram at right, she wrote the equation

Is Randi’s equation valid? Explain your thinking.

Notice the right angle.

Yes, she used the Pythagorean Theorem.

To solve her equation, first rewrite

by multiplying . You may want to review the Math Notes box for Lesson 2.2.2. Now solve your equation for

. Use a generic rectangle to multiply the binomials.

What is the perimeter of Randi’s triangle?

Use the value of

to determine the length of each side of the triangle.