Question

Find the square of the following number without multiplication.

$35$

Answer 1

${35}^2=(30+5{)}^2$

$={30}^2+2\left(30\right)\left(5\right)+5^2$ [Using the identity $(a+b{)}^2=a^2+b^2+2ab$]

$=900+300+25$

$=1225$

Hence, ${35}^2=1225$