SOLUTION: Could someone please help me with this equation? I cant seem to solve it. Solve for x {{{25x^2=13}}}

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Question 100440: Could someone please help me with this equation? I cant seem to solve it.
Solve for x
25x%5E2=13
Found 2 solutions by Nate, edjones:
Answer by Nate(3500) About Me  (Show Source):
You can put this solution on YOUR website!
25x%5E2=13
.
25x%5E2%2F25=13%2F25
.
x%5E2=13%2F25
.
sqrt%28x%5E2%29=sqrt%2813%2F25%29
.
x=sqrt%2813%29%2Fsqrt%2825%29
.
x=sqrt%2813%29%2F5 which is positive and negative

Answer by edjones(8007) About Me  (Show Source):
You can put this solution on YOUR website!
25x%5E2=13
25x^2-13=0
Solved by pluggable solver: SOLVE quadratic equation (work shown, graph etc)
Quadratic equation ax%5E2%2Bbx%2Bc=0 (in our case 25x%5E2%2B0x%2B-13+=+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=%280%29%5E2-4%2A25%2A-13=1300.

Discriminant d=1300 is greater than zero. That means that there are two solutions: +x%5B12%5D+=+%28-0%2B-sqrt%28+1300+%29%29%2F2%5Ca.

x%5B1%5D+=+%28-%280%29%2Bsqrt%28+1300+%29%29%2F2%5C25+=+0.721110255092798
x%5B2%5D+=+%28-%280%29-sqrt%28+1300+%29%29%2F2%5C25+=+-0.721110255092798

Quadratic expression 25x%5E2%2B0x%2B-13 can be factored:
25x%5E2%2B0x%2B-13+=+%28x-0.721110255092798%29%2A%28x--0.721110255092798%29
Again, the answer is: 0.721110255092798, -0.721110255092798. Here's your graph:
graph%28+500%2C+500%2C+-10%2C+10%2C+-20%2C+20%2C+25%2Ax%5E2%2B0%2Ax%2B-13+%29