# Formulas Exercises

### Example 1

The formula for the area of a circle is *A* = π*r*^{2}. What do the letters *A* and *r* represent?

### Example 2

The formula for the area of a circle is *A *= π*r*^{2}. Which is the dependent and which is the independent variable?

### Example 3

The formula for the area of a circle is *A* = π*r*^{2}. Let *H* be the area of half a circle. Write a formula describing *H* in terms of *r*.