SOLUTION: use the quadratic formula to solve -16y^2 -8y + 3 =0

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Question 118520: use the quadratic formula to solve
-16y^2 -8y + 3 =0
Answer by solver91311(24713) About Me  (Show Source):
You can put this solution on YOUR website!
-16y%5E2+-8y+%2B+3+=0

Solved by pluggable solver: SOLVE quadratic equation with variable
Quadratic equation ax%5E2%2Bbx%2Bc=0 (in our case -16x%5E2%2B-8x%2B3+=+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=%28-8%29%5E2-4%2A-16%2A3=256.

Discriminant d=256 is greater than zero. That means that there are two solutions: +x%5B12%5D+=+%28--8%2B-sqrt%28+256+%29%29%2F2%5Ca.

x%5B1%5D+=+%28-%28-8%29%2Bsqrt%28+256+%29%29%2F2%5C-16+=+-0.75
x%5B2%5D+=+%28-%28-8%29-sqrt%28+256+%29%29%2F2%5C-16+=+0.25

Quadratic expression -16x%5E2%2B-8x%2B3 can be factored:
-16x%5E2%2B-8x%2B3+=+-16%28x--0.75%29%2A%28x-0.25%29
Again, the answer is: -0.75, 0.25. Here's your graph:
graph%28+500%2C+500%2C+-10%2C+10%2C+-20%2C+20%2C+-16%2Ax%5E2%2B-8%2Ax%2B3+%29