SOLUTION: Can you please help me solve 5x squared+16x-20=0 by factoring? It's due tomorrow thank you.

Algebra ->  Quadratic Equations and Parabolas -> SOLUTION: Can you please help me solve 5x squared+16x-20=0 by factoring? It's due tomorrow thank you.      Log On


   

Question 938879: Can you please help me solve 5x squared+16x-20=0 by factoring? It's due tomorrow thank you.
Answer by ewatrrr(24785) About Me  (Show Source):
You can put this solution on YOUR website!
5x^2 + 16x - 20 = 0
Solved by pluggable solver: SOLVE quadratic equation with variable
Quadratic equation ax%5E2%2Bbx%2Bc=0 (in our case 5x%5E2%2B16x%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=%2816%29%5E2-4%2A5%2A-20=656.

Discriminant d=656 is greater than zero. That means that there are two solutions: +x%5B12%5D+=+%28-16%2B-sqrt%28+656+%29%29%2F2%5Ca.

x%5B1%5D+=+%28-%2816%29%2Bsqrt%28+656+%29%29%2F2%5C5+=+0.961249694973139
x%5B2%5D+=+%28-%2816%29-sqrt%28+656+%29%29%2F2%5C5+=+-4.16124969497314

Quadratic expression 5x%5E2%2B16x%2B-20 can be factored:
5x%5E2%2B16x%2B-20+=+5%28x-0.961249694973139%29%2A%28x--4.16124969497314%29
Again, the answer is: 0.961249694973139, -4.16124969497314. Here's your graph:
graph%28+500%2C+500%2C+-10%2C+10%2C+-20%2C+20%2C+5%2Ax%5E2%2B16%2Ax%2B-20+%29