SOLUTION: Use the quadratic formula to solve the equation 4x^2 - 36x = 48

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Question 108757: Use the quadratic formula to solve the equation
4x^2 - 36x = 48
Answer by elima(1433) About Me  (Show Source):
You can put this solution on YOUR website!
Solved by pluggable solver: SOLVE quadratic equation (work shown, graph etc)
Quadratic equation ax%5E2%2Bbx%2Bc=0 (in our case 4x%5E2%2B-36x%2B-48+=+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=%28-36%29%5E2-4%2A4%2A-48=2064.

Discriminant d=2064 is greater than zero. That means that there are two solutions: +x%5B12%5D+=+%28--36%2B-sqrt%28+2064+%29%29%2F2%5Ca.

x%5B1%5D+=+%28-%28-36%29%2Bsqrt%28+2064+%29%29%2F2%5C4+=+10.1789083458003
x%5B2%5D+=+%28-%28-36%29-sqrt%28+2064+%29%29%2F2%5C4+=+-1.17890834580027

Quadratic expression 4x%5E2%2B-36x%2B-48 can be factored:
4x%5E2%2B-36x%2B-48+=+%28x-10.1789083458003%29%2A%28x--1.17890834580027%29
Again, the answer is: 10.1789083458003, -1.17890834580027. Here's your graph:
graph%28+500%2C+500%2C+-10%2C+10%2C+-20%2C+20%2C+4%2Ax%5E2%2B-36%2Ax%2B-48+%29

:)