SOLUTION: How would i solve this equation in radical and decimal form 2n^2-11n-76=0?

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Question 690252: How would i solve this equation in radical and decimal form 2n^2-11n-76=0?
Answer by ReadingBoosters(3246) About Me  (Show Source):
You can put this solution on YOUR website!
Solved by pluggable solver: SOLVE quadratic equation with variable
Quadratic equation an%5E2%2Bbn%2Bc=0 (in our case 2n%5E2%2B-11n%2B-76+=+0) has the following solutons:

n%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=%28-11%29%5E2-4%2A2%2A-76=729.

Discriminant d=729 is greater than zero. That means that there are two solutions: +x%5B12%5D+=+%28--11%2B-sqrt%28+729+%29%29%2F2%5Ca.

n%5B1%5D+=+%28-%28-11%29%2Bsqrt%28+729+%29%29%2F2%5C2+=+9.5
n%5B2%5D+=+%28-%28-11%29-sqrt%28+729+%29%29%2F2%5C2+=+-4

Quadratic expression 2n%5E2%2B-11n%2B-76 can be factored:
2n%5E2%2B-11n%2B-76+=+2%28n-9.5%29%2A%28n--4%29
Again, the answer is: 9.5, -4. Here's your graph:
graph%28+500%2C+500%2C+-10%2C+10%2C+-20%2C+20%2C+2%2Ax%5E2%2B-11%2Ax%2B-76+%29