Exercise 5 Page 115

To solve an equation, we should first gather all of the variable terms on one side of the equation and all of the constant terms on the other side using the Properties of Equality. In this case, the variable r is already on the left-hand side of the equation, so we will start by subtracting 9 from both sides.

The solution to the equation is r=- 53. We can check our solution by substituting it into the original equation.

Since the left-hand side is equal to the right-hand side, our solution is correct.