Question

Find the product:

(9x + 5y)(4x + 3y)

Answer 1

$$\begin{gathered} (9\mathrm{x}+5\mathrm{y})(4\mathrm{x}+3\mathrm{y}) \\ =9\mathrm{x}\times (4\mathrm{x}+3\mathrm{y})+5\mathrm{y}\times (4\mathrm{x}+3\mathrm{y}) \\ =(9\mathrm{x}\times 4\mathrm{x}+9\mathrm{x}\times 3\mathrm{y})+(5\mathrm{y}\times 4\mathrm{x}+5\mathrm{y}\times 3\mathrm{y}) \\ =36{\mathrm{x}}^2+27\mathrm{xy}+20\mathrm{xy}+15{\mathrm{y}}^2 \\ =36{\mathrm{x}}^2+47\mathrm{xy}+15{\mathrm{y}}^2 \end{gathered}$$