(x-3)^2+x(x+9)=x^2-6x+9+x^2+9x=2x^2+3x+9
(2a+5)^2-5(4a+5)=4a^2+20a+25-20a-25=4a^2
9b(b-1)-(3b+2)^2=9b^2-9b-9b^2-12b-4=-21b-4
(b-4)^2+(b-1)(2-b)=b^2-8b+16+2b-b^2-2+b=-5b+14
(a+3)(5-a)-(a-1)^2=5a-a^2+15-3a-a^2+2a-1=-2a^2+4a+14
(5+2y)(y-3)-(5-2y)^2=5y-15+2y^2-6y-25+20y-4y^2=-2y^2+19y-40