Question

Using distributive law find the square of 101 and 72

Answer 1

$$\begin{gathered} {\left(101\right)}^2 \\ =101\times 101 \\ =101\times \left(100+1\right) \\ =101\times 100+101\times 1\{\mathrm{using}\mathrm{distributive}\mathrm{law}\mathrm{a}\times \left(\mathrm{b}+\mathrm{c}\right)=\mathrm{a}\times \mathrm{b}+\mathrm{a}\times \mathrm{c}\} \\ =10100+101 \\ =10201 \\ {\left(72\right)}^2 \\ =72\times 72 \\ =72\times \left(70+2\right) \\ =72\times 70+72\times 2 \\ =5040+144 \\ =5184 \end{gathered}$$
Therefore square of 101 is 10201 and square of 72 is 5184.