Answer:
[tex]\huge \boxed{49x^2 y^2 -126x^2 y +81x^2}[/tex]
Step-by-step explanation:
[tex]\sf (9x - 7xy)^2[/tex]
Expanding brackets.
[tex]\sf (9x - 7xy)(9x-7xy)[/tex]
Applying the FOIL method.
[tex]\sf 9x(9x-7xy)-7xy(9x-7xy)[/tex]
[tex]\sf 81x^2 -63x^2 y -63x^2 y+49x^2 y^2[/tex]
Combining like terms.
[tex]\sf 81x^2 -126x^2 y+49x^2 y^2[/tex]
