# Evaluating Formulas by Substitution Exercises

### Example 1

Zach has a rectangular living room that measures 10 feet wide by 20 feet long. He has thought about bringing in some furniture, but he doesn't want to spoil the perfect rectangularness of it. In order to cover the floor of his living room with carpet, how many square feet of carpet does Zach need?

### Example 2

Zach has a rectangular living room that measures 10 feet wide by 20 feet long. He has thought about bringing in some furniture, but he doesn't want to spoil the perfect rectangularness of it. How much trim will Zach need if he is to put trim all around the edge of the floor?

### Example 3

What is the area of the triangle shown below? No fair guessing. We know what a lucky guesser you are.