Given: An expression
[tex](2y-9x)^2[/tex]Required: To simplify the expression.
Explanation: Recall the algebraic identity-
[tex](a-b)^2=a^2+b^2-2ab[/tex]Using the identity, we can simplify it as follows-
[tex](2y-9x)^2=(2y)^2+(9x)^2-2(2y)(9x)[/tex]Further simplifying-
[tex]=4y^2+81x^2-36xy[/tex]Final Answer: The simplified expression is-
[tex]4y^2+81x^2-36xy[/tex]
