#1
a²+9a²-6ab+b²=10a²-6ab+b²
9b²-(a²-6ab+9b²)=9b²-a²+6ab-9b²=-a²+6ab
25a²+70ab+49b²-70ab=25a²+49b²
64a²-16ab+b²-64a²=b²-16ab
#2
25+10y+y²+y²-7y=2y²+3y+25
4a-a²+16-8a+a²=-4a+16
x²-16x+64-2x(36-12x+x²)=x²-16x+64-72x+24x²-2x³=-2x³+25x²-88x+64
c²+7c-(1-2c+c²)=c²+7c-1+2c-c²=9c-1
#3
2(a²-2ab+b²)=2a²-4ab+2b²
a(1+4a+4a²)a+4a²+4a³
-6(4x²-4xy+y²)=-24x²-6y²+24xy
-y(9x²-6xy+y²)=-9x²y+6xy²-y³=-y³-9x²y+6xy²
#1
(a-3b)²+(3a+b)²=a²-6ab+9b²+9a²+6ab+b²=
10a²+10b²
(x+2y)²-(x-2y)²=x²+4xy+4y²-(x²-4xy+4y²)=
x²+4xy+4y²-x²+4xy-4y²=8xy
#2
#1
(3a+4b)²+(3a-2b)8b=9a²+24ab+16b²+24ab-16b²=9a²+48ab=3a(3a+16b)
#2
(6a-2)²-(5a+2)²=36a²-24a+4-(25a²+20a+4)=36a²-24a+4-25a²-20a-4=
11a²-44a=11a(a-4)
число-x
x²-квадрат числа
x+3-увеличили
(x+3)²-x²=39
x²+6x+9-x²=39
6x=39-9
6x=30|:6
x=5