1. 8-4B Solving Quadratic Equations when the Leading Coefficient isn’t 1.
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

2. 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.

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

4. 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.
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Do not discard the GMF from step 2.
Check using FOIL.

5. Solve by factoring. 3
- 3 -3
- 1 -1 -4
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6. 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?
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Set the factors equal to zero and solve.

7. White Board Practice

8. 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?
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9. 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
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10. 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
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11. 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.
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12. 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?
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13. Homework
8-A10 Pages # 23–30,54-59.