SOLUTION: I need to solve this equation with the quadratic formula. {{{m^2+12m+5=0}}} What i got was -6 + or - Squareroot of 31 I have done this twice but i seem to get it wrong every ti

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Question 254294: I need to solve this equation with the quadratic formula.
m%5E2%2B12m%2B5=0
What i got was -6 + or - Squareroot of 31
I have done this twice but i seem to get it wrong every time then i also got -12 + or - squareroot of 31 and that was wrong to please help me.
Found 4 solutions by Alan3354, richwmiller, stanbon, JimboP1977:
Answer by Alan3354(69443) About Me  (Show Source):
You can put this solution on YOUR website!
m%5E2%2B12m%2B5=0
Solved by pluggable solver: SOLVE quadratic equation (work shown, graph etc)
Quadratic equation ax%5E2%2Bbx%2Bc=0 (in our case 1x%5E2%2B12x%2B5+=+0) has the following solutons:

x%5B12%5D+=+%28b%2B-sqrt%28+b%5E2-4ac+%29%29%2F2%5Ca

For these solutions to exist, the discriminant b%5E2-4ac should not be a negative number.

First, we need to compute the discriminant b%5E2-4ac: b%5E2-4ac=%2812%29%5E2-4%2A1%2A5=124.

Discriminant d=124 is greater than zero. That means that there are two solutions: +x%5B12%5D+=+%28-12%2B-sqrt%28+124+%29%29%2F2%5Ca.

x%5B1%5D+=+%28-%2812%29%2Bsqrt%28+124+%29%29%2F2%5C1+=+-0.432235637169978
x%5B2%5D+=+%28-%2812%29-sqrt%28+124+%29%29%2F2%5C1+=+-11.56776436283

Quadratic expression 1x%5E2%2B12x%2B5 can be factored:
1x%5E2%2B12x%2B5+=+%28x--0.432235637169978%29%2A%28x--11.56776436283%29
Again, the answer is: -0.432235637169978, -11.56776436283. Here's your graph:
graph%28+500%2C+500%2C+-10%2C+10%2C+-20%2C+20%2C+1%2Ax%5E2%2B12%2Ax%2B5+%29

----------------
It's
m = -6 ± sqrt(31)

Answer by richwmiller(17219) About Me  (Show Source):
You can put this solution on YOUR website!

The right answer is no prettier than your answer.
Solved by pluggable solver: SOLVE quadratic equation with variable
Quadratic equation am%5E2%2Bbm%2Bc=0 (in our case 1m%5E2%2B12m%2B5+=+0) has the following solutons:

m%5B12%5D+=+%28b%2B-sqrt%28+b%5E2-4ac+%29%29%2F2%5Ca

For these solutions to exist, the discriminant b%5E2-4ac should not be a negative number.

First, we need to compute the discriminant b%5E2-4ac: b%5E2-4ac=%2812%29%5E2-4%2A1%2A5=124.

Discriminant d=124 is greater than zero. That means that there are two solutions: +x%5B12%5D+=+%28-12%2B-sqrt%28+124+%29%29%2F2%5Ca.

m%5B1%5D+=+%28-%2812%29%2Bsqrt%28+124+%29%29%2F2%5C1+=+-0.432235637169978
m%5B2%5D+=+%28-%2812%29-sqrt%28+124+%29%29%2F2%5C1+=+-11.56776436283

Quadratic expression 1m%5E2%2B12m%2B5 can be factored:
1m%5E2%2B12m%2B5+=+1%28m--0.432235637169978%29%2A%28m--11.56776436283%29
Again, the answer is: -0.432235637169978, -11.56776436283. Here's your graph:
graph%28+500%2C+500%2C+-10%2C+10%2C+-20%2C+20%2C+1%2Ax%5E2%2B12%2Ax%2B5+%29

Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
solve this equation with the quadratic formula.
m^2+12m+5 = 0
---
Form: m = [-b +- sqrt(b^2-4ac)]/(2a)
---
Your Problem:
m = [-12 +- sqrt(144 - 4*1*5)]/(2)
---
m = [-12 +- sqrt(124)]/2
---
m = [-12 +- sqrt(4*31)]/2
---
m = [-12 +- 2sqrt(31)]/2
---
m = -6 +- sqrt(31)
==========================
Cheers,
Stan H.

Answer by JimboP1977(311) About Me  (Show Source):
You can put this solution on YOUR website!
m+=+%28-b+%2B-+sqrt%28+b%5E2-4%2Aa%2Ac+%29%29%2F%282%2Aa%29+
m=%28-12+%2B-+sqrt%28144-%284%2A1%2A5%29%29%29%2F2
m=-6+%2B-+sqrt%28144-20%29%2F2
m=-6+%2B-+sqrt%28124%29%2F2
m=-6+%2B-+sqrt%28124%29%2F2
m=-6+%2B-+sqrt%2831%29
USing the solver:
Solved by pluggable solver: SOLVE quadratic equation with variable
Quadratic equation ax%5E2%2Bbx%2Bc=0 (in our case 1x%5E2%2B12x%2B5+=+0) has the following solutons:

x%5B12%5D+=+%28b%2B-sqrt%28+b%5E2-4ac+%29%29%2F2%5Ca

For these solutions to exist, the discriminant b%5E2-4ac should not be a negative number.

First, we need to compute the discriminant b%5E2-4ac: b%5E2-4ac=%2812%29%5E2-4%2A1%2A5=124.

Discriminant d=124 is greater than zero. That means that there are two solutions: +x%5B12%5D+=+%28-12%2B-sqrt%28+124+%29%29%2F2%5Ca.

x%5B1%5D+=+%28-%2812%29%2Bsqrt%28+124+%29%29%2F2%5C1+=+-0.432235637169978
x%5B2%5D+=+%28-%2812%29-sqrt%28+124+%29%29%2F2%5C1+=+-11.56776436283

Quadratic expression 1x%5E2%2B12x%2B5 can be factored:
1x%5E2%2B12x%2B5+=+1%28x--0.432235637169978%29%2A%28x--11.56776436283%29
Again, the answer is: -0.432235637169978, -11.56776436283. Here's your graph:
graph%28+500%2C+500%2C+-10%2C+10%2C+-20%2C+20%2C+1%2Ax%5E2%2B12%2Ax%2B5+%29