[tex]\bf \left( \cfrac{~~\begin{matrix} 8 \\[-0.7em]\cline{1-1}\\[-5pt]\end{matrix}~~\cdot 4\cdot 2}{~~\begin{matrix} 8 \\[-0.7em]\cline{1-1}\\[-5pt]\end{matrix}~~\cdot 7} \right)^2 \times\left( \cfrac{8^0}{7^{-3}} \right)^3\times 7^{-9}\implies \left( \cfrac{4\cdot 2}{7} \right)^2 \times \left( \cfrac{1}{7^{-3}} \right)^3\times 7^{-9}[/tex]
[tex]\bf \left( \cfrac{8}{7} \right)^2 \times \left( \cfrac{1^3}{7^{-3\cdot 3}} \right)\times 7^{-9}\implies \left( \cfrac{8^2}{7^2} \right) \times \left( \cfrac{1}{7^{-9}} \right)\times 7^{-9}\implies \cfrac{8^2}{7^2}\times \cfrac{7^{-9}}{7^{-9}} \\\\\\ \cfrac{8^2}{7^2}\cdot 1\implies \cfrac{8^2}{7^2}\implies \cfrac{64}{49}[/tex]
