SOLUTION: Solution of 15x2 - 24x - 132 = 0

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Question 769926: Solution of 15x2 - 24x - 132 = 0
Answer by ramkikk66(644) About Me  (Show Source):
You can put this solution on YOUR website!
15%2Ax%5E2+-+24%2Ax+-+132+=+0 Dividing by 3
5%2Ax%5E2+-+8%2Ax+-+44+=+0
Solve using the inbuilt quadratic solver in this site:


 
Solved by pluggable solver: SOLVE quadratic equation with variable


Quadratic equation ax%5E2%2Bbx%2Bc=0 (in our case 5x%5E2%2B-8x%2B-44+=+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=%28-8%29%5E2-4%2A5%2A-44=944.
  
  Discriminant d=944 is greater than zero. That means that there are two solutions: +x%5B12%5D+=+%28--8%2B-sqrt%28+944+%29%29%2F2%5Ca.
  
    x%5B1%5D+=+%28-%28-8%29%2Bsqrt%28+944+%29%29%2F2%5C5+=+3.87245829914744
    x%5B2%5D+=+%28-%28-8%29-sqrt%28+944+%29%29%2F2%5C5+=+-2.27245829914744
    
    Quadratic expression 5x%5E2%2B-8x%2B-44 can be factored:
  5x%5E2%2B-8x%2B-44+=+5%28x-3.87245829914744%29%2A%28x--2.27245829914744%29
  Again, the answer is: 3.87245829914744, -2.27245829914744.
Here's your graph:

graph%28+500%2C+500%2C+-10%2C+10%2C+-20%2C+20%2C+5%2Ax%5E2%2B-8%2Ax%2B-44+%29