question_answer

Using distributive law, find the square of 43.

Answer:

43 = 40 + 3

So,   \[{{43}^{2}}={{\left( 40+3 \right)}^{2~}}~~~\]

= (40 + 3) (40 + 3)

= 40(40 + 3) + 3(40 + 3)

\[=40\times 40+40\times 3+3\times 40+3\times 3\]

= 1600 +240+9

=1849

So,      \[{{43}^{2}}=\text{ }1849~\]