Question

1) (2x-3y)(4x+3y)+(3x+4y)(4y-3x)
2) (y-8)(2y-1)-(3y+1)(5y-2)

Answer 1

1) 8x^2+6xy-12xy-9y^2+12xy-9x^2+16y^2-12xy=-x^2+7y^2-6xy
2) 2y^2-y-16y+8-15y^2+6y-5y+2=-13y^2-16y+10