DAY 4 ­ Completing the Square, a = 1 NOTES.notebook
October 24, 2014
HW: Worksheet
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EXTRA HELP Today ­ D220 at 2:40
UNIT 2, 3, or 4 TEST RETAKES BY FRIDAY, 11/7
UNIT 4 TEST ON THURSDAY, 10/30
EXTRA CREDIT DUE BY FRIDAY, 11/7 (IN CLASS)
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DAY 4 ­ Completing the Square, a = 1 NOTES.notebook
October 24, 2014
Learning Goal: What are the steps to completing the square on a quadratic equation?
DO NOW: Factor the Following Trinomials
• What do you notice about all of these factors?
1) x2 + 10x + 25
2) x2 + 4x + 4
3) x2 ­ 6x + 9
4) x2 ­ 8x + 16
These trinomials are called perfect square trinomials.
Whenever you multiply a binomial by itself twice, the resulting trinomial is called a perfect square trinomial.
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DAY 4 ­ Completing the Square, a = 1 NOTES.notebook
October 24, 2014
Learning Goal: What are the steps to completing the square on a quadratic equation?
• How can we create perfect square trinomials?
Before
After
x2 + 10x x2 + 10x + 25
x2 + 4x x2 + 4x + 4
x2 ­ 6x x2 ­ 6x + 9
x2 ­ 8x x2 ­ 8x + 16
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DAY 4 ­ Completing the Square, a = 1 NOTES.notebook
October 24, 2014
Learning Goal: What are the steps to completing the square on a quadratic equation?
WARM­UP
• How can we create perfect square trinomials?
• What value of "c" will give you a perfect square trinomial?
x2 ­ 12x + c 4
DAY 4 ­ Completing the Square, a = 1 NOTES.notebook
October 24, 2014
Why do we need to know how to complete the square?
Solve for x: x2 + 6x + 4 = 0
1) "a" coefficient must equal 1. (divide all terms by "a")
2) Move "c" coefficient to the other side. (isolate x­terms)
3) Take and add to each side. (create a perfect square trinomial)
4) Factor the perfect square trinomial
5) Solve for x (look to simplify/reduce if possible)
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DAY 4 ­ Completing the Square, a = 1 NOTES.notebook
October 24, 2014
Learning Goal: What are the steps to completing the square on a quadratic equation?
Ex 1: Solve for x by completing the square: x2 + 6x + 4 = 0
Take 6
DAY 4 ­ Completing the Square, a = 1 NOTES.notebook
October 24, 2014
Learning Goal: What are the steps to completing the square on a quadratic equation?
Ex 2: Solve y2 ­ 4y = ­12 for y, in simplest a + bi form,
by completing the square.
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DAY 4 ­ Completing the Square, a = 1 NOTES.notebook
October 24, 2014
Learning Goal: What are the steps to completing the square on a quadratic equation?
Ex 3: Solve m2 ­ 24 = ­10m for m by completing the square.
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DAY 4 ­ Completing the Square, a = 1 NOTES.notebook
October 24, 2014
Learning Goal: What are the steps to completing the square on a quadratic equation?
CLASSWORK
Solve x2 + 8 = ­8x for x, in simplest radical form, by completing the square.
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