Multiply.
-$$( 7 x y + 8 z ) ( 7 x y - 8 z )$$
A) $49 x ^ { 2 } y ^ { 2 } - 112 x y z - 64 z ^ { 2 }$
B) $x ^ { 2 } y ^ { 2 } - 64 z ^ { 2 }$
C) $49 x ^ { 2 } y ^ { 2 } + 112 x y z - 64 z ^ { 2 }$
D) $49 x ^ { 2 } y ^ { 2 } - 64 z ^ { 2 }$

Question

Quizplus · Accepted Answer

This is an application of the difference of squares formula, $a^2 - b^2 = (a + b)(a - b)$. Here, $a = 7xy$ and $b = 8z$, so the product is $49x^2y^2 - 64z^2$.

Multiply - (7xy+8z)(7xy−8z)( 7 x y + 8 z ) ( 7 x y - 8 z )(7xy+8z)(7xy−8z)

Multiply
- $( 7 x y + 8 z ) ( 7 x y - 8 z )$