SOLUTION: x^2+4x+8=0 solve by using quadratic formula

Algebra ->  Quadratic Equations and Parabolas  -> Quadratic Equations Lessons  -> Quadratic Equation Lesson -> SOLUTION: x^2+4x+8=0 solve by using quadratic formula      Log On


   

Question 486051: x^2+4x+8=0 solve by using quadratic formula
Answer by Edwin McCravy(20054) About Me  (Show Source):
You can put this solution on YOUR website!
x%5E2%2B4x%2B8=0

Compare to

ax%5E2%2Bbx%2Bc=0

a=1, b=4, c=8

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

x+=+%28-%284%29+%2B-+sqrt%28+%284%29%5E2-4%2A%281%29%2A%288%29+%29%29%2F%282%2A%281%29%29+ 

x+=+%28-4+%2B-+sqrt%2816-32+%29%29%2F2+

x+=+%28-4+%2B-+sqrt%28-16+%29%29%2F2+

x+=+%28-4+%2B-+i%2Asqrt%2816+%29%29%2F2+

x+=+%28-4+%2B-+i%2A4%29%2F2+

x+=+%28-4+%2B-+4i%29%2F2+

x+=+%28-4%29%2F2+%2B-+%284i%29%2F2+

x+=+-2+%2B-+2i+

Two conjugate imaginary solutions:  -2 + 2i and -2 - 2i
 
Edwin