$(4x+5y)\;(5y+4x)$

$(8x^2-3x)(8x^2-3x)$

$(4p+5q)(4q+5p)$

$(8x^2-3x)(3x+8x^2)$

$(-x-3y)(-3y-x)$

$(\frac34m-2n)(\frac43m-2n)$

$16a^2-16ab+4b^2$

$\frac14a^2-4ab+4b^2$

$25a^2+50ab-4b^2$