SOLUTION: Solve the equation: 4x^3+3x^2=64x+48 *Please show work :) Thank you!

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Question 604629: Solve the equation: 4x^3+3x^2=64x+48
*Please show work :) Thank you!
Found 2 solutions by jim_thompson5910, lwsshak3:
Answer by jim_thompson5910(35256) About Me  (Show Source):
You can put this solution on YOUR website!
4x^3+3x^2=64x+48

4x^3+3x^2-64x-48=0

(4x^3+3x^2)+(-64x-48)=0

x^2(4x+3)+(-64x-48)=0

x^2(4x+3)-16(4x+3)=0

(x^2-16)(4x+3)=0

(x-4)(x+4)(4x+3)=0

I'll let you take it from here.

Answer by lwsshak3(11628) About Me  (Show Source):
You can put this solution on YOUR website!
Solve the equation:
4x^3+3x^2=64x+48
Try grouping
x^2(4x+3)=16(4x+3)
set to zero
x^2(4x+3)-16(4x+3)=0
factor out (4x+3)
(4x+3)(x^2-16)=0
solve for x
4x+3=0
4x=-3
x=-3/4
or
x^2-16=0
(x+4)(x-4)=0 (difference of squares)
x=-4
and
x=4
roots or zeros are: -3/4, -4 and 4