Question

multiply.
$(3x^{4})(-2x^{7})(3x^{9})$
$(3x^{4})(-2x^{7})(3x^{9})=\square$ (simplify your answer.)

Explanation:

Step1: Multiply the coefficients

$3 \times (-2) \times 3 = -18$

Step2: Add exponents of $x$

$x^{4+7+9} = x^{20}$

Step3: Combine coefficient and variable

$-18 \times x^{20}$

Answer:

$-18x^{20}$