## Presentation on theme: "8-4B Solving Quadratic Equations when the Leading Coefficient isn’t 1."— Presentation transcript:

X-Factor method If you factor out a GMF: before using the X figure, keep it, after using the X figure, discard it. Algebra Glencoe McGraw-Hill Linda Stamper

In the previous lesson you factored quadratic trinomials when the leading coefficient wasn’t 1. Today you will use the factors to solve quadratic equations. To solve a quadratic equation set the factors equal to zero and then solve the equations.

Do not confuse instructions. Make sure you understand what it means to:
Solve Factor

Can you factor out a greatest monomial factor?
Solve. You must keep the greatest monomial factor that is pulled out before using the X figure! -10 - 5 -5 + 2 2 -3 Can you factor out a greatest monomial factor? Set the factors equal to zero and solve. ( )( ) Do not discard the GMF from step 2. Check using FOIL.

Solve by factoring. 3 - 3 -3 - 1 -1 -4 ( )( )

Can you factor out a greatest monomial factor?
Example 1 Solve. 6 + 3 3 + 2 2 5 Can you factor out a greatest monomial factor? ( )( ) Set the factors equal to zero and solve.

White Board Practice

Example 2 Solve. Example 3 Solve. -22 -18 + 22 22 - 1 -1 21 + 6 6 - 3
-3 Can you factor out a greatest monomial factor? 3 Can you factor out a greatest monomial factor? ( )( ) ( )( )

Example 5 Solve. Example 4 Solve. 6 60 + 6 6 + 1 1 - 10 -10 -6 - 6 7
Can you factor out a greatest monomial factor? Can you factor out a greatest monomial factor? 7 -16 ( )( ) ( )( )

Example 7 Solve. Example 6 Solve. 18 -12 + 6 6 + 3 3 + 4 4 - 3 -3 9 1
Can you factor out a greatest monomial factor? Can you factor out a greatest monomial factor? + 4 4 - 3 -3 9 1 ( )( ) ( )( )

Can you factor out a greatest monomial factor?
Example 8 Solve. You must keep the greatest monomial factor that is pulled out before using the X figure! -10 - 5 -5 + 2 2 -3 Can you factor out a greatest monomial factor? Set the factors equal to zero and solve. ( )( )

Example 9 Solve. Example 10 Solve. 36 -12 + 9 9 + 4 4 - 6 -6 + 2 2 13
Can you factor out a greatest monomial factor? 13 -4 Can you factor out a greatest monomial factor? ( )( ) ( )( )

Homework 8-A10 Pages # 23–30,54-59.