SOLUTION: 3x^2 + 2x = 7 x^2 + 8x+9=-7 Thank You:-)

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Question 108734: 3x^2 + 2x = 7

x^2 + 8x+9=-7


Thank You:-)
Answer by elima(1433) About Me  (Show Source):
You can put this solution on YOUR website!
3x^2 + 2x = 7
Solved by pluggable solver: SOLVE quadratic equation (work shown, graph etc)
Quadratic equation ax%5E2%2Bbx%2Bc=0 (in our case 3x%5E2%2B2x%2B-7+=+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=%282%29%5E2-4%2A3%2A-7=88.

Discriminant d=88 is greater than zero. That means that there are two solutions: +x%5B12%5D+=+%28-2%2B-sqrt%28+88+%29%29%2F2%5Ca.

x%5B1%5D+=+%28-%282%29%2Bsqrt%28+88+%29%29%2F2%5C3+=+1.23013858660781
x%5B2%5D+=+%28-%282%29-sqrt%28+88+%29%29%2F2%5C3+=+-1.89680525327448

Quadratic expression 3x%5E2%2B2x%2B-7 can be factored:
3x%5E2%2B2x%2B-7+=+%28x-1.23013858660781%29%2A%28x--1.89680525327448%29
Again, the answer is: 1.23013858660781, -1.89680525327448. Here's your graph:
graph%28+500%2C+500%2C+-10%2C+10%2C+-20%2C+20%2C+3%2Ax%5E2%2B2%2Ax%2B-7+%29

x^2 + 8x+9=-7
Solved by pluggable solver: SOLVE quadratic equation (work shown, graph etc)
Quadratic equation ax%5E2%2Bbx%2Bc=0 (in our case 1x%5E2%2B8x%2B2+=+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=%288%29%5E2-4%2A1%2A2=56.

Discriminant d=56 is greater than zero. That means that there are two solutions: +x%5B12%5D+=+%28-8%2B-sqrt%28+56+%29%29%2F2%5Ca.

x%5B1%5D+=+%28-%288%29%2Bsqrt%28+56+%29%29%2F2%5C1+=+-0.258342613226059
x%5B2%5D+=+%28-%288%29-sqrt%28+56+%29%29%2F2%5C1+=+-7.74165738677394

Quadratic expression 1x%5E2%2B8x%2B2 can be factored:
1x%5E2%2B8x%2B2+=+%28x--0.258342613226059%29%2A%28x--7.74165738677394%29
Again, the answer is: -0.258342613226059, -7.74165738677394. Here's your graph:
graph%28+500%2C+500%2C+-10%2C+10%2C+-20%2C+20%2C+1%2Ax%5E2%2B8%2Ax%2B2+%29

:)