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## #1 2006-07-29 13:11:08

MathsIsFun
Registered: 2005-01-21
Posts: 7,664

### Completing The Square

Complete the Square for the following:

1. x[sup]2[/sup] + 10x + 21

2. 2x[sup]2[/sup] + 7x + 4

"The physicists defer only to mathematicians, and the mathematicians defer only to God ..."  - Leon M. Lederman

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## #2 2006-07-29 14:06:33

Zhylliolom
Real Member
Registered: 2005-09-05
Posts: 412

### Re: Completing The Square

3. x² -10x + 16.

4. 2x² - 3x + 4.

Bonus:

5. Complete the square for both x and y, to find the standard equation for this circle:

x² - 6x + y² - 4y + 9 = 0.

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## #3 2006-07-31 19:08:57

Devantè
Real Member
Registered: 2006-07-14
Posts: 6,400

### Re: Completing The Square

6. x² + x + -3.75 = 0
7. x² + 5x + 6 = 0
8. x² + 2x + 1 = 0
9. x² + 3x + -10 = 0
10. m² + -4m + -21 = 0
11. 3k² + 18k + 15 = 0
12. 2n² + -22n + 60 = 0
13. 4y² + 8y + -21 = 0
14. 8y² + 10y + -3 = 0
15. 50k² + -20k + -6 = 0
16. 100x² + -100x + 9 = 0
17. 10t² = t + 2
18. 18m² + 6m + 6 = 6m² + 30m + -3
19. p² + -0.75p + 0.125 = 0
20. 2x² = x² + 1.75 + -3x
21. x² = 0.6x + -0.08
22. 3y² + -2.55y + -1.0 = 0.5
23. j² + -3.5j + 1.5 = 0
24. c² + 3.75c + -1 = 0
25. w² + 10.1w + 1 = 0
26. x² + -11.5x + -6 = 0

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## #4 2006-09-29 21:54:51

justlookingforthemoment
Moderator
Registered: 2005-05-26
Posts: 2,161

### Re: Completing The Square

Complete the following using fractions, not decimals.

27. x² + 3x + 1

28. x² - x - 7

29. x² + 5x - 2

30. x² - 29x - 7

31. x² - 7x +9

32. x² + 13x + 17

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## #5 2007-11-15 14:23:43

iamtheshoveler
Member
Registered: 2007-10-19
Posts: 1

### Re: Completing The Square

MathsIsFun wrote:

Complete the Square for the following:

1. x[sup]2[/sup] + 10x + 21

2. 2x[sup]2[/sup] + 7x + 4

the answer to 1. is -3, -7

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## #6 2007-11-15 14:37:43

iamtheshoveler
Member
Registered: 2007-10-19
Posts: 1

### Re: Completing The Square

how do you get the answers to these problems?

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## #7 2008-04-06 14:52:05

jum
Member
Registered: 2008-04-06
Posts: 0

### Re: Completing The Square

What is the basic way to complete the square?

Last edited by jum (2008-04-06 15:03:40)

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MathsIsFun