SOLUTION: 1/x^2+8/x+15=0

Algebra ->  Quadratic Equations and Parabolas  -> Quadratic Equations Lessons  -> Quadratic Equation Lesson -> SOLUTION: 1/x^2+8/x+15=0      Log On


   

Question 662243: 1/x^2+8/x+15=0
Answer by ewatrrr(24785) About Me  (Show Source):
You can put this solution on YOUR website!
 

Hi,

1%2Fx%5E2%2B8%2Fx%2B15=0  |Multiplying thru by x^2 so as all denominators = 1

  1 + 8x + 15x^2 = 0

15x^2 + 8x + 1 = 0  || Standard form ax^2 + bx + c = 0

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

x+=+%28-8+%2B-+sqrt%2864-60%29%29%2F%2830%29+

x+=+%28-8+%2B-+2%29%2F%2830%29+

   x = -10/30 = -3  0r   x = -6/30 = -1/5