Ответ:
Объяснение:
1.
a) (2x-b)(3x+b)+(3b-x)(b+x)=
=6x²-b²+3b²-x²=
=5x²+2b²
b) (c+2)(c-3)-(c+1)(c+3)=
=c²-6-(c²+3)=
=c²-6-c²-3=
=-9
B) (y-10)(y-2)+(y+4)(y-5)=
=y²+20+y²-20=
=2y²
r) (a-5)(a+1)-(a-6)(a-1)=
=a²-5-(a²+6)=
=a²-5-a²-6=
=-11
2.
a) (b+3)(b-3)+(2b+3)²=
=b²-9+4b²+12b+9=
=5b²+12b
a) 3(x-5)²+(10x-8x²)=
=3(x²+25)+10x-8x²=
=3x²+75+10x-8x²=
=-5x²+75+10x
Остальное не видно до конца))