SOLUTION: How do I solve for x in this equation? 8x^2 – 49 = 0

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Question 311355: How do I solve for x in this equation?
8x^2 – 49 = 0
Answer by JBarnum(2146) About Me  (Show Source):
You can put this solution on YOUR website!
use quadratic equation
Solved by pluggable solver: SOLVE quadratic equation with variable
Quadratic equation ax%5E2%2Bbx%2Bc=0 (in our case 8x%5E2%2B0x%2B-49+=+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%2A8%2A-49=1568.

Discriminant d=1568 is greater than zero. That means that there are two solutions: +x%5B12%5D+=+%28-0%2B-sqrt%28+1568+%29%29%2F2%5Ca.

x%5B1%5D+=+%28-%280%29%2Bsqrt%28+1568+%29%29%2F2%5C8+=+2.47487373415292
x%5B2%5D+=+%28-%280%29-sqrt%28+1568+%29%29%2F2%5C8+=+-2.47487373415292

Quadratic expression 8x%5E2%2B0x%2B-49 can be factored:
8x%5E2%2B0x%2B-49+=+8%28x-2.47487373415292%29%2A%28x--2.47487373415292%29
Again, the answer is: 2.47487373415292, -2.47487373415292. Here's your graph:
graph%28+500%2C+500%2C+-10%2C+10%2C+-20%2C+20%2C+8%2Ax%5E2%2B0%2Ax%2B-49+%29