Question

Subtract the square of 42 from the square of 43 without actually calculating the squares. ​

Answer 1

Answer:

Given,

We need to Subtract the square of 42 from the square of 43 without actually calculating the squares.

Using the formula

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

We get....

$= > {(43)}^{2} - {(42)}^{2} \\ = > (43 + 42)(43 - 42) \\ = > 85 \times 1 \\ = > 85.$

Answer 2

Step-by-step explanation:

Using the formula

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

We get....

43^2 - 42^2

43 + 42 × 43-42

= 85