Объяснение:
1) a) 25x²+10xy+y²
b) x⁴-2x²y²+y⁴
2) a) (3a+2c)(9a²-6ac+4c²)
b) (3x-4)²
3) x³-2x²+2x²-4x+4x+8-x³+9x=26
8+9x=26
9x=18
x=2
4) x²-2x+1+7>=x²+8x+16
x²-x²-2x-8x+8-16>=0
-10x>=8
x>=-0,8
5) x+y=55 x=55-y
x²-y²=275 (x+y)(x-y)=275
55(x-y)=275
x-y=5
55-y-y=5
-2y=-50
y=25
x=55-25=30
