А)(3m-a)(a+3m)-(a-2m)=9m²-a²-a+2m=8m²-a
B)(1+2a)²-(4a+2)(a-1)
1+4a²-4a²+4a-2a+2=2a+3
C)(5x-2y)(x+y)-5x²=5x²+5xy-2yx+2y²-5x²=5xy-2yx+2y²
D)3(x-4)(x+2)+(3x-1)(5-x)=3x-4(x+2)+15x-3x²-5+x=3x-4x-8+15x-3x²-5+x=15x-3x²-13
E)(b-5)(7-5b)-2(b+2)(b-6)=7b-5b²-35+25b-2b-4(b-6)=7b-5b²-35+25b-2b-4b+24=26b-5b²+10