SOLUTION: solve using a graphing calculator x^2+x=-1/4

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Question 170240: solve using a graphing calculator x^2+x=-1/4
Answer by Alan3354(69443) About Me  (Show Source):
You can put this solution on YOUR website!
solve using a graphing calculator x^2+x=-1/4
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x^2 + x + 0.25 = 0
I don't have a graphing calculator, and I don't see how you would be able to see it if I did.
Solved by pluggable solver: SOLVE quadratic equation (work shown, graph etc)
Quadratic equation ax%5E2%2Bbx%2Bc=0 (in our case 1x%5E2%2B1x%2B0.25+=+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=%281%29%5E2-4%2A1%2A0.25=0.

Discriminant d=0 is zero! That means that there is only one solution: x+=+%28-%281%29%29%2F2%5C1.
Expression can be factored: 1x%5E2%2B1x%2B0.25+=+%28x--0.5%29%2A%28x--0.5%29

Again, the answer is: -0.5, -0.5. Here's your graph:
graph%28+500%2C+500%2C+-10%2C+10%2C+-20%2C+20%2C+1%2Ax%5E2%2B1%2Ax%2B0.25+%29

x = -1/2