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

To solve,

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

a² - b² = (a + b) (a - b)

a = 22

b = 21

so,

(22 + 21)(22 - 21)

43(1)

= 43