Question 146510
{{{(-7x^3)*(20x^9)}}} Start with the given expression.



{{{-140x^3 x^9}}} Multiply the coefficients {{{-7}}} and {{{20}}} to get {{{-140}}}



{{{-140x^(3+9)}}} When you multiply monomials, simply add the exponents.



{{{-140x^12}}} Add.



So {{{(-7x^3)*(20x^9)=-140x^12}}}.