1)x²-2x+1=(x-1)²
2)9-12t+4t²=3²-12t+(2t)²=(3-2t)²
3)y²+y+(1/4)=y²+y+(1/2)²=(y+(1/2))²
4)25m²-80m+64=(5m)²-80m+8²=(5m-8)²
5)(x²/4)+xy+y²=(x/2)²+xy+y²=((x/2)+y)²
6)a²b²-4ab+4=(ab)²-4ab+2²=(ab-2)²
1)x²-2x+1=(x-1)²
2)9-12t+4t²=3²-12t+(2t)²=(3-2t)²
3)y²+y+(1/4)=y²+y+(1/2)²=(y+(1/2))²
4)25m²-80m+64=(5m)²-80m+8²=(5m-8)²
5)(x²/4)+xy+y²=(x/2)²+xy+y²=((x/2)+y)²
6)a²b²-4ab+4=(ab)²-4ab+2²=(ab-2)²