Question 475773

{{{c^3-3c^2-54c}}}

={{{c(c^2-3c-54)}}}....replace {{{-3c}}} with {{{-9c+6c}}}

={{{c(c^2-9c+6c-54)}}}.......group

={{{c((c^2-9c)+(6c-54))}}}

={{{c(c(c-9)+6(c-9))}}}

={{{c(c+6)(c-9)}}}