Question

$\text{Simplify}(6-5xy)(6+5xy)\text{using an}$ $\text{algebraic identity.}$

• A. $18-5x^2{y}^2$
• B. $36-25x^2{y}^2$
• C. $36-24x^2{y}^2$
• D. $36-25x^{2}y$

Answer 1

The correct option is B $36-25x^2{y}^2$

$\text{To simplify :}(6-5xy)(6+5xy)$

Using the identity,
$(a-b)(a+b)=a^2-b^2$

$(6-5xy)(6+5xy)=(6{)}^2-(5xy{)}^2$
$=36-25x^2{y}^2$