The Quadratic Formula

Each of the problems below is a link. If you click on the problem, it will take you to a YouTube video of a full, step-by-step solution for the problem. You may try these problems as practice and use the videos to check your answer, or you can just watch the videos to see more worked-out example problems.

Derivation of the quadratic formula: x equals the opposite of b, + or minus the square root of b squared minus 4a c, all over 2a
Use the quadratic formula to solve: x squared minus 2x minus 4 = 0
Use the quadratic formula to solve: 3x squared + 3x minus 1 = 0
Use the quadratic formula to solve: 18y squared minus 7y = 1
Use the quadratic formula to solve: z squared + 9 = 10z
Use the quadratic formula to solve: t squared = t + 8
Use the quadratic formula to solve: 8x squared + x minus 9 = 0
Use the quadratic formula to solve: x squared minus 4x + 5 = 0
Use the quadratic formula to solve: 4n squared + 4n + 5 = 0
Use the quadratic formula to solve: 9x squared minus 4x + 1 = 0