Exercise 45 Page 87

To solve the equation we have to isolate $b$ on one side. We will use the Multiplication Property of Equality to multiply both sides of the equation by 7. This will eliminate the division and isolate $b.$ To check that this solution is correct, substitute $b=\text{-}77$ into the original equation and simplify. Since the left-hand side and right-hand side are equal, $b=\text{-}77$ is the correct solution.