SOLUTION: Ok this one has completely stumped me: i am only coming up with two answers but the answer in the back of the book says three different answers: HELP!! 4x^3+24x^2+12x-40=0;-2 Th

Algebra ->  Polynomials-and-rational-expressions -> SOLUTION: Ok this one has completely stumped me: i am only coming up with two answers but the answer in the back of the book says three different answers: HELP!! 4x^3+24x^2+12x-40=0;-2 Th      Log On


   

Question 134924: Ok this one has completely stumped me: i am only coming up with two answers but the answer in the back of the book says three different answers: HELP!!
4x^3+24x^2+12x-40=0;-2 The problem says use synthetic division to show the number given to the right of the equation is in fact a solution and then solve the polynomial.
Thank you in advance!!
Answer by scott8148(6628) About Me  (Show Source):
You can put this solution on YOUR website!
since -2 is a zero (root), x+2 is a factor

4x^3+24x^2+12x-40=0 __ (x+2)(4x^2+16x-20)=0

dividing by 4 and factoring __ (x+2)(x+5)(x-1)=0