C²-16=(c-4)(c+4)
(2x-1)² =4x²-4x+1
(x+3y)²=x²+6xy+9y²
16x²-25=(4x-5)(4x +5)
x²+4x+4=(x+2)²
(0.2-x)(0,2+x)=0.04-x²
(0.5-x)²=0.25-1x+x²
x²+9=(x+3)(x-3)
(11-x)(x+11)=122-x²
-8x+x²+16=(x+4)²
(y-x⁴)(y+x⁴)
(x⁴-y)(x⁴+y)
25x²+10x+1=(5x+1)²
-a²-2ab-b²=-(a+b)²
1-c³=(1-c)(1-2c-c²)
-x²-2x-1=-(x+1)²
(a-4)(a²+4a+16)=a³-4³
(a+6)(a²-6a+36)=a³+6³