Question

Percy solved the equation x2 + 7x + 12 = 12. His work is shown below. Is Percy correct? Explain. 1. (x + 3)(x + 4) = 12 2. x + 3 = 12 or x + 4 = 12 3. x = 9 or x = 8

Answer 1

Sample Response: Percy is not correct because he applied the zero product property to a factored expression that was not equal to 0. He should have subtracted 12 from both sides to get x2 + 7x = 0 before factoring. The correct solutions are 0 and -7.

Answer 2

Percy is not correct because he applied the zero product property to a factored expression that was not equal to 0. He should have subtracted 12 from both sides to get x2 + 7x = 0 before factoring. The correct solutions are 0 and -7.