SOLUTION: solve this quadratic equation but don't use the quadratic formula 4x^2+12x+5=0

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Question 704404: solve this quadratic equation but don't use the quadratic formula
4x^2+12x+5=0

Answer by Stitch(470) About Me  (Show Source):
You can put this solution on YOUR website!
First find the factors of 4 form the 4X%5E2
The factors of 4 are: 1,2,2,4
Next Find the factors of 5 (the constant)
The factors of 5 are: 1,5
Note that the 5 is positive that means that the factors have to both be positive or both negative.
Now use the factors of 4 and the factors of 5 to come up with the 12X
2*5 + 2*1 = 12
So 4X%5E2+%2B+12X+%2B+5 can be rewritten as %282X+%2B+5%29%2A%282X+%2B+1%29
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Now we have to solve for each part of the equation.
The equation equals zero when either of the parentheses equal zero.
2X+%2B+5+=+0
Subtract 5 from both sides
2X+=+-5
Divide both sides by 2
highlight%28X+=+-5%2F2%29
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2X+%2B+1+=+0
Subtract 1 from both sides
2X+=+-1
Divide both sides by 2
highlight_green%28X+=+-1%2F2%29