SOLUTION: What is the answer to 6x^2+7x-20=0

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Question 40742: What is the answer to 6x^2+7x-20=0
Answer by Nate(3500) About Me  (Show Source):
You can put this solution on YOUR website!
6x%5E2+%2B+7x+-+20+=+0
x+=+%28-b+%2B-+sqrt%28+b%5E2-4%2Aa%2Ac+%29%29%2F%282%2Aa%29+
x+=+%28-7+%2B-+sqrt%28+%287%29%5E2-4%2A%286%29%2A%28-20%29+%29%29%2F%282%2A%286%29%29+
x+=+%28-7+%2B-+sqrt%28+49+%2B+480+%29%29%2F%2812%29+
x+=+%28-7+%2B-+sqrt%28++529+%29%29%2F%2812%29+
x+=+%28-7+%2B-+23%29%2F%2812%29+
x+=+-2.5 or x+=+4%2F3
or
Solved by pluggable solver: SOLVE quadratic equation with variable
Quadratic equation ax%5E2%2Bbx%2Bc=0 (in our case 6x%5E2%2B7x%2B-20+=+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=%287%29%5E2-4%2A6%2A-20=529.

Discriminant d=529 is greater than zero. That means that there are two solutions: +x%5B12%5D+=+%28-7%2B-sqrt%28+529+%29%29%2F2%5Ca.

x%5B1%5D+=+%28-%287%29%2Bsqrt%28+529+%29%29%2F2%5C6+=+1.33333333333333
x%5B2%5D+=+%28-%287%29-sqrt%28+529+%29%29%2F2%5C6+=+-2.5

Quadratic expression 6x%5E2%2B7x%2B-20 can be factored:
6x%5E2%2B7x%2B-20+=+6%28x-1.33333333333333%29%2A%28x--2.5%29
Again, the answer is: 1.33333333333333, -2.5. Here's your graph:
graph%28+500%2C+500%2C+-10%2C+10%2C+-20%2C+20%2C+6%2Ax%5E2%2B7%2Ax%2B-20+%29