Your answer is already correct but you can use your calculator to check if your answer is correct if you are unsure. If your calculator is a Casio FX-97SG X, you press the menu button on the calculator and select 5 for equations, then select 2 for polynomial and select 2 for degree. It also works with x to the power of 3 and 4 by selecting 3 and 4 for degree respectively