Question

Evaluate using suitable identities
181 square - 19 square

Answer 1

${181}^{2} - {19}^{2}$

$= (181 + 19) \times (181 - 19)$

$= 200 \times 162$

$= 32400$

This was evaluated by using the identity :

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

where,

$a = 181 \: and \: b = 19$

Answer 2

$\textbf{\huge{ANSWER:}}$

$\sf{To\:solve:}$

$181^{2} - 19^{2}$

Now, we know by identity that:-

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

We need to use the same identity here as well !

For solving, we can put the values as:-

a = 181
b = 19

Now that we've obtained the values, put the values in the identity and then simply solve it;

$181^{2} - 19^{2} = ( 181 - 19 ) ( 181 + 19 )$

Adding and subtracting the same way as given, we get:-

=》 162 × 200

Multiply and Get you answer as;

=》 $\textbf{32400}$

There's your answer :)