Question 78619
The given expression is: 


{{{15x^3 - 4x^2 - 4x = 0 }}} 


{{{15x^3 - 10x^2 + 6x^2 - 4x = 0 }}} 


{{{ 5x^2(3x - 2) + 2x(3x - 2) = 0 }}}  



{{{(5x^2 + 2x)(3x - 2)= 0 }}}


==> {{{(5x^2 + 2x) = 0 }}} or 3x - 2 = 0 


==> x(5x + 2) = 0  or (3x - 2) = 0  


==> x = 0 or (5x + 2) =  0     or 3x = 2


==> x = 0 or 5x = -2    or x = 2/3 


==> x = 0  or x = -5/2  or x = 2/3 



Since the given polynomial is a cubic polynomial we get 3 roots and the roots are: 


x = 0, x = -5/2, x = 2/3 


Hence, the solution.