SOLUTION: 4x^2=5+8x

Algebra ->  Quadratic Equations and Parabolas  -> Quadratic Equations Lessons  -> Quadratic Equation Lesson -> SOLUTION: 4x^2=5+8x      Log On


   

Question 607228: 4x^2=5+8x
Answer by jim_thompson5910(35256) About Me  (Show Source):
You can put this solution on YOUR website!
4x%5E2=5%2B8x

4x%5E2-5-8x+=+0

4x%5E2-8x-5+=+0

Now use the quadratic formula to solve for x

x+=+%28-b%2B-sqrt%28b%5E2-4ac%29%29%2F%282a%29

x+=+%28-%28-8%29%2B-sqrt%28%28-8%29%5E2-4%284%29%28-5%29%29%29%2F%282%284%29%29

x+=+%288%2B-sqrt%2864-%28-80%29%29%29%2F%288%29

x+=+%288%2B-sqrt%28144%29%29%2F8

x+=+%288%2Bsqrt%28144%29%29%2F8 or x+=+%288-sqrt%28144%29%29%2F8

x+=+%288%2B12%29%2F8 or x+=+%288-12%29%2F8

x+=+20%2F8 or x+=+-4%2F8

x+=+5%2F2 or x+=+-1%2F2

So the solutions are x+=+5%2F2 or x+=+-1%2F2
--------------------------------------------------------------------------------------------------------------
If you need more help, email me at jim_thompson5910@hotmail.com

Also, please consider visiting my website: http://www.freewebs.com/jimthompson5910/home.html and making a donation. Thank you

Jim
--------------------------------------------------------------------------------------------------------------