## Elementary Algebra

$18xy^4$
RECALL: (i) $\dfrac{a^m}{a^n} = a^{m-n}$ (ii) $a^0=1, a\ne0$ Divide the coefficients, and then use the rule(s) above to obtain: $=18x^{2-1}y^{6-2} \\=18x^{1}y^4 \\=18xy^4$