SOLUTION: x^2-19x+90=0 Solve by using quadratic formula

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Question 40442: x^2-19x+90=0
Solve by using quadratic formula
Answer by Nate(3500) About Me  (Show Source):
You can put this solution on YOUR website!
x%5E2-19x%2B90=0
Solved by pluggable solver: SOLVE quadratic equation with variable
Quadratic equation ax%5E2%2Bbx%2Bc=0 (in our case 1x%5E2%2B-19x%2B90+=+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=%28-19%29%5E2-4%2A1%2A90=1.

Discriminant d=1 is greater than zero. That means that there are two solutions: +x%5B12%5D+=+%28--19%2B-sqrt%28+1+%29%29%2F2%5Ca.

x%5B1%5D+=+%28-%28-19%29%2Bsqrt%28+1+%29%29%2F2%5C1+=+10
x%5B2%5D+=+%28-%28-19%29-sqrt%28+1+%29%29%2F2%5C1+=+9

Quadratic expression 1x%5E2%2B-19x%2B90 can be factored:
1x%5E2%2B-19x%2B90+=+1%28x-10%29%2A%28x-9%29
Again, the answer is: 10, 9. Here's your graph:
graph%28+500%2C+500%2C+-10%2C+10%2C+-20%2C+20%2C+1%2Ax%5E2%2B-19%2Ax%2B90+%29