SOLUTION: here is the problem : Find the roots of the quadratic , equadratic equation 2timesXsquare plus 9x-8=0.using quadratic formula.

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Question 235406: here is the problem : Find the roots of the quadratic , equadratic equation 2timesXsquare plus 9x-8=0.using quadratic formula.
Answer by Alan3354(69443) About Me  (Show Source):
You can put this solution on YOUR website!
Find the roots of the quadratic , equadratic equation 2timesXsquare plus 9x-8=0.using quadratic formula.
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2x%5E2+%2B+9x+-+8+=+0
Solved by pluggable solver: SOLVE quadratic equation with variable
Quadratic equation a0%5E2%2Bb0%2Bc=0 (in our case 20%5E2%2B90%2B-8+=+0) has the following solutons:

0%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=%289%29%5E2-4%2A2%2A-8=145.

Discriminant d=145 is greater than zero. That means that there are two solutions: +x%5B12%5D+=+%28-9%2B-sqrt%28+145+%29%29%2F2%5Ca.

0%5B1%5D+=+%28-%289%29%2Bsqrt%28+145+%29%29%2F2%5C2+=+0.760398644698074
0%5B2%5D+=+%28-%289%29-sqrt%28+145+%29%29%2F2%5C2+=+-5.26039864469807

Quadratic expression 20%5E2%2B90%2B-8 can be factored:
20%5E2%2B90%2B-8+=+2%280-0.760398644698074%29%2A%280--5.26039864469807%29
Again, the answer is: 0.760398644698074, -5.26039864469807. Here's your graph:
graph%28+500%2C+500%2C+-10%2C+10%2C+-20%2C+20%2C+2%2Ax%5E2%2B9%2Ax%2B-8+%29