Question

Find the product:-(7x+11y)(7x-11y)

Answer 1

Answer:

$\left(7x+11y\right)\left(7x-11y\right):\quad 49x^2-121y^2$

Step-by-step explanation:

$\left(7x+11y\right)\left(7x-11y\right)$

$\mathrm{Apply\:Difference\:of\:Two\:Squares\:Formula:\:}\left(a+b\right)\left(a-b\right)=a^2-b^2$ $a=7x,\:b=11y$

$=\left(7x\right)^2-\left(11y\right)^2$

$\mathrm{Simplify}\:\left(7x\right)^2-\left(11y\right)^2$

$\left(7x\right)^2-\left(11y\right)^2$

$\mathrm{Apply\:exponent\:rule}:\quad \left(a\cdot \:b\right)^n=a^nb^n$

$=7^2x^2-\left(11y\right)^2$

$\mathrm{Apply\:exponent\:rule}:\quad \left(a\cdot \:b\right)^n=a^nb^n$

$=7^2x^2-11^2y^2$

$\mathrm{Refine}$

$=49x^2-121y^2$

Answer 2

Step-by-step explanation:

(7x+11y)(7x-11y)

by using identity:(a+b)(a-b)=(a^2)-(b^2)

(7x)^2-(11y)^2

49x^2-121y^2