SOLUTION: state the descriminant for x^2+3x-4

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Question 260892: state the descriminant for x^2+3x-4
Found 2 solutions by richwmiller, drk:
Answer by richwmiller(17219) About Me  (Show Source):
You can put this solution on YOUR website!
Solved by pluggable solver: SOLVE quadratic equation with variable
Quadratic equation ax%5E2%2Bbx%2Bc=0 (in our case 1x%5E2%2B3x%2B-4+=+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=%283%29%5E2-4%2A1%2A-4=25.

Discriminant d=25 is greater than zero. That means that there are two solutions: +x%5B12%5D+=+%28-3%2B-sqrt%28+25+%29%29%2F2%5Ca.

x%5B1%5D+=+%28-%283%29%2Bsqrt%28+25+%29%29%2F2%5C1+=+1
x%5B2%5D+=+%28-%283%29-sqrt%28+25+%29%29%2F2%5C1+=+-4

Quadratic expression 1x%5E2%2B3x%2B-4 can be factored:
1x%5E2%2B3x%2B-4+=+1%28x-1%29%2A%28x--4%29
Again, the answer is: 1, -4. Here's your graph:
graph%28+500%2C+500%2C+-10%2C+10%2C+-20%2C+20%2C+1%2Ax%5E2%2B3%2Ax%2B-4+%29

Answer by drk(1908) About Me  (Show Source):
You can put this solution on YOUR website!
here is the original expression
x%5E2%2B3x-4
The discriminant is
D+=+b%5E2-4ac
or
D+=+3%5E2-4%2A1%2A%28-4%29
which is
D+=+9%2B16
or
D+=+25