SOLUTION: 2vsquared-5v-25=0

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Question 242415: 2vsquared-5v-25=0
Found 2 solutions by philline_palana, checkley77:
Answer by philline_palana(20) About Me  (Show Source):
You can put this solution on YOUR website!
Solved by pluggable solver: SOLVE quadratic equation with variable
Quadratic equation av%5E2%2Bbv%2Bc=0 (in our case 2v%5E2%2B-5v%2B-25+=+0) has the following solutons:

v%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=%28-5%29%5E2-4%2A2%2A-25=225.

Discriminant d=225 is greater than zero. That means that there are two solutions: +x%5B12%5D+=+%28--5%2B-sqrt%28+225+%29%29%2F2%5Ca.

v%5B1%5D+=+%28-%28-5%29%2Bsqrt%28+225+%29%29%2F2%5C2+=+5
v%5B2%5D+=+%28-%28-5%29-sqrt%28+225+%29%29%2F2%5C2+=+-2.5

Quadratic expression 2v%5E2%2B-5v%2B-25 can be factored:
2v%5E2%2B-5v%2B-25+=+2%28v-5%29%2A%28v--2.5%29
Again, the answer is: 5, -2.5. Here's your graph:
graph%28+500%2C+500%2C+-10%2C+10%2C+-20%2C+20%2C+2%2Ax%5E2%2B-5%2Ax%2B-25+%29

Answer by checkley77(12844) About Me  (Show Source):
You can put this solution on YOUR website!
2v^2-5v-25=0
(2v+5)(v-5)=0
2v+5=0
2v=-5
v=-5/2
v=-2.5 ans.
v-5=0
v=5