Question 672968

{{{7b^3-6b^2+21b-18}}}..rearrange the terms 


{{{7b^3+21b-6b^2-18}}}..... group


{{{(7b^3+21b)-(6b^2+18)}}}


{{{7b(b^2+3)-6(b^2+3)}}}


{{{(7b-6)(b^2+3)}}}