$$\begin{aligned}12xy&\\ 71x-31x^{2}-24x^{3}-21^{\frac{7}{9}}(38x):&\end{aligned}$$
$-9261\left(3-8x\right)^{8}-24x^{3}-31x^{2}+716x$
$-155373797376x^{8}+466121392128x^{7}-611784327168x^{6}+458838245376x^{5}-215080427520x^{4}+64524128232x^{3}-12098274079x^{2}+1296244364x-60761421$
