SOLUTION: x^2+4x+2=0

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Question 264874: x^2+4x+2=0
Answer by JBarnum(2146) About Me  (Show Source):
You can put this solution on YOUR website!
x%5E2%2B4x%2B2=0
Do the quadratic formula where Ax%5E2%2BBx%2BC=0 A=1 B=4 C=2
x= -0.585786437626905 or -3.41421356237309.
Solved by pluggable solver: SOLVE quadratic equation with variable
Quadratic equation ax%5E2%2Bbx%2Bc=0 (in our case 1x%5E2%2B4x%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=%284%29%5E2-4%2A1%2A2=8.

Discriminant d=8 is greater than zero. That means that there are two solutions: +x%5B12%5D+=+%28-4%2B-sqrt%28+8+%29%29%2F2%5Ca.

x%5B1%5D+=+%28-%284%29%2Bsqrt%28+8+%29%29%2F2%5C1+=+-0.585786437626905
x%5B2%5D+=+%28-%284%29-sqrt%28+8+%29%29%2F2%5C1+=+-3.41421356237309

Quadratic expression 1x%5E2%2B4x%2B2 can be factored:
1x%5E2%2B4x%2B2+=+1%28x--0.585786437626905%29%2A%28x--3.41421356237309%29
Again, the answer is: -0.585786437626905, -3.41421356237309. Here's your graph:
graph%28+500%2C+500%2C+-10%2C+10%2C+-20%2C+20%2C+1%2Ax%5E2%2B4%2Ax%2B2+%29