Question

Find the product:

(5x + 7)(3x + 4)

Answer 1

$$\begin{gathered} (5\mathrm{x}+7)(3\mathrm{x}+4) \\ =5\mathrm{x}\times (3\mathrm{x}+4)+7\times (3\mathrm{x}+4) \\ =(5\mathrm{x}\times 3\mathrm{x}+5\mathrm{x}\times 4)+(7\times 3\mathrm{x}+7\times 4) \\ =15{\mathrm{x}}^2+20\mathrm{x}+21\mathrm{x}+28 \\ =15{\mathrm{x}}^2+41\mathrm{x}+28 \end{gathered}$$