Question

solve using identities (11x-13y)(11x+13y)​

Answer 1

Answer:

Using identity

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

So answer will be

${(11x)}^{2} - {(13y) }^{2}$

$111 {x }^{2} - 169 {y}^{2}$

Answer 2

$\huge\mathcal\colorbox{lightgreen}{{\color{black}{AnSwEr~↓~↓~}}}$

$\bf \green {To \: solve: } \: (11x - 13y)(11x + 13y) \\ \bf \green{using \: suitable \: identities} \\ \\ \bf Here \: the \: equation \: can \: be \\ \bf re - arranged \: as: \\ \underline{ \underline{ \bf(11x + 13y)(11x - 13y)}} \\ \\ \bf Identity \: to \: be \: used : \\ \bf (a + b)(a - b) = a^{2} - b^{2} \\ \bf here: \: a = 11x \: \: \: \: \: b = 13y \\ \bf \therefore (11x + 13y)(11x - 13y) \\ \bf= {(11x)}^{2} - {(13y)}^{2} \\ \bf = \green{ \underline{ \boxed{ \bf \: 121 {x}^{2} - 169 {y}^{2} } \: }}$

$\huge\green{\textbf{\textsf{Hope~it~helps..!!}}}$