Can some one help with transformation rules

Factor the monomial completely 42a3b3

Plz hurry evaluate the expression a+b where a=8 and b=19

Answer asap! show all work! find the number of complex roots, the possible number of real roots and the possible rational roots of the polynomial function. then, solve for all roots. x^3 + 2x^2 + 3x + 6 = 0