(с+2)(с-3)-(с-1)= c -3с+2с-6-(с -2с+1) = с - с -6 -с +2с-1= с-7
3ab²-3ac²=3a(b²-c²)
100c^8-81c^5=c^5(100c³-81)
162ay²-2a²y=2ay(81y-a)
-5b²+5=5(-b²+1)
14p²-1=-1(-14p²+1)
32x³y²-2x²y=2x²y(16xy-1)
12x²y+12xy+3y²x=3xy(4x+4+y)
7x³y²-3xy²-18x²y=xy(7x²y-3y-18x)
ab²-2ab+a=a(b²-2b+1)
100x²y²+20xy-x³y⁴=xy(100xy+20-x²y³)
=49a^2+14ab-8b^2-b^2+b^2=(
49a^2+14ab+b^2)-9b^2=(7a+b)^2-9b^2 =(7a+b-3b)(7a+b+3b)=(7a-2b)(7a+4b)