SOLUTION: I need help in factoring 21x^2-59x+8

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Question 873639: I need help in factoring 21x^2-59x+8
Answer by ewatrrr(24785) About Me  (Show Source):
You can put this solution on YOUR website!
21x^2-59x+8
Solved by pluggable solver: SOLVE quadratic equation with variable
Quadratic equation ax%5E2%2Bbx%2Bc=0 (in our case 21x%5E2%2B-59x%2B8+=+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=%28-59%29%5E2-4%2A21%2A8=2809.

Discriminant d=2809 is greater than zero. That means that there are two solutions: +x%5B12%5D+=+%28--59%2B-sqrt%28+2809+%29%29%2F2%5Ca.

x%5B1%5D+=+%28-%28-59%29%2Bsqrt%28+2809+%29%29%2F2%5C21+=+2.66666666666667
x%5B2%5D+=+%28-%28-59%29-sqrt%28+2809+%29%29%2F2%5C21+=+0.142857142857143

Quadratic expression 21x%5E2%2B-59x%2B8 can be factored:
21x%5E2%2B-59x%2B8+=+21%28x-2.66666666666667%29%2A%28x-0.142857142857143%29
Again, the answer is: 2.66666666666667, 0.142857142857143. Here's your graph:
graph%28+500%2C+500%2C+-10%2C+10%2C+-20%2C+20%2C+21%2Ax%5E2%2B-59%2Ax%2B8+%29