Solving Quadratic Equations by Factoring January 6, 2015 Pages 48-49
Warm-Up – pg. 48(left side) Factor the following expressions: x 2 + 2x – 99 x 2 – 5x 7x x + 6
Objective solve quadratic equations and inequalities using graphs, tables, and algebraic methods.[8.D]
Title – pg. 49 (Right Side) Solving Quadratic Equations by Factoring
Essential Question How do I use what I already know about factoring to find the solutions to a quadratic equation?
To Solve Quadratic Equations by Factoring: Set the equation equal to 0. Factor the side of the equation not equal to zero. Set each factor equal to 0 and solve each equation to find your values for x. Check by plugging in each answer to the original equation!
Example 1 x 2 = x + 30
Example 2 3x 2 – 8 = 10x
Example 3 x 2 – 2x = 0
Example 4 8x + 24 = 2x 2
Example 5 8x 2 – 5x = 2x 2 + 6x – 4
Common Mistakes quadratic-equation-by-factoring quadratic-equation-by-factoring 0:41 – 2:05
Think about it… (Reflection) How are your answers related to the simplified fractions you use when factoring?