Step-by-step explanation:
given the expression
[tex]x^22y^4(x^2 - 16) - 9y^4(x^4 - 16)[/tex]
we proceed by opening the brackets
[tex]x^2y^4(x^2 - 16) - 9y^4(x^4 - 16) \\\\x^4y^4-16x^2y^4-9x^4y^4+144y^4\\\\[/tex]
collet like terms we have
[tex]x^4y^4-16x^2y^4-9x^4y^4+144y^4 \\\\x^4y^4-9x^4y^4-16x^2y^4+144y^4 \\\\8x^4y^4-16x^2y^4+144y^4[/tex]
factoring we have
[tex]8x^4y^4-16x^2y^4+144y^4\\\\8y^4(x^4-2x^2)+144y^4[/tex]
