SOLUTION: 5x2 = -10x - 2

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Question 343276: 5x2 = -10x - 2
Answer by edjones(8007) About Me  (Show Source):
You can put this solution on YOUR website!
5x2 = -10x - 2
5x^2+10x+2=0
x=-1-(sqrt(15)/5), x=-1+sqrt(15)/5 See below
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Ed
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Solved by pluggable solver: SOLVE quadratic equation with variable
Quadratic equation ax%5E2%2Bbx%2Bc=0 (in our case 5x%5E2%2B10x%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=%2810%29%5E2-4%2A5%2A2=60.

Discriminant d=60 is greater than zero. That means that there are two solutions: +x%5B12%5D+=+%28-10%2B-sqrt%28+60+%29%29%2F2%5Ca.

x%5B1%5D+=+%28-%2810%29%2Bsqrt%28+60+%29%29%2F2%5C5+=+-0.225403330758517
x%5B2%5D+=+%28-%2810%29-sqrt%28+60+%29%29%2F2%5C5+=+-1.77459666924148

Quadratic expression 5x%5E2%2B10x%2B2 can be factored:
5x%5E2%2B10x%2B2+=+5%28x--0.225403330758517%29%2A%28x--1.77459666924148%29
Again, the answer is: -0.225403330758517, -1.77459666924148. Here's your graph:
graph%28+500%2C+500%2C+-10%2C+10%2C+-20%2C+20%2C+5%2Ax%5E2%2B10%2Ax%2B2+%29