MATH 110 Lecture Notes - Lecture 27: Negative Number
Document Summary
A quadratic equation is an equation that could be written as ax 2 + bx + c = 0 when a 0. There are three basic methods for solving quadratic equations: factoring, using the quadratic formula, and completing the square. Solve x 2 6 x = 16. Following the steps, x 2 6 x = 16 becomes x 2 6 x 16 = 0. Factor. ( x 8)( x + 2) = 0. Both values, 8 and 2, are solutions to the original equation. Solve y 2 = 6 y 5. Setting all terms equal to zero, y 2 + 6 y + 5 = 0. Factor. ( y + 5)( y + 1) = 0. To check, y 2 = 6 y 5. A quadratic with a term missing is called an incomplete quadratic (as long as the ax 2 term isn"t missing). To check, x 2 16 = 0. Solve x 2 + 6 x = 0.
