Question

Subtract the square of 21 from the square of 22 without actually calculating the squares. ​

Answer 1

Answer:

Given,

We need to Subtract the square of 21 from the square of 22 without actually calculating the squares.

Using the formula

${x}^{2} - {y}^{2} = (x + y)(x - y)$

We get.....

$= > {(22)}^{2} - {(21)}^{2} \\ = > (22 + 21)(22 - 21) \\ = > 43 \times 1 \\ = > 43.$

Answer 2

Answer:

${a}^{2} - {b}^{2} = ( a+b )(a -b )$

${(22)}^{2} - {(21)}^{2} =( 22 + 21)(22 - 21) \\ \\ = > 43 \times 1 \\ \\ = > 43$