Take out the constants.
\[81{x}^{2}-(2\times 81\times 10)x{x}^{2}{y}^{3}\]
Simplify \(2\times 81\) to \(162\).
\[81{x}^{2}-(162\times 10)x{x}^{2}{y}^{3}\]
Simplify \(162\times 10\) to \(1620\).
\[81{x}^{2}-1620x{x}^{2}{y}^{3}\]
Use Product Rule: \({x}^{a}{x}^{b}={x}^{a+b}\).
\[81{x}^{2}-1620{x}^{1+2}{y}^{3}\]
Simplify \(1+2\) to \(3\).
\[81{x}^{2}-1620{x}^{3}{y}^{3}\]
81*x^2-1620*x^3*y^3
