[tex](a\pm b)^2=a^2\pm2ab+b^2[/tex]
[tex]A.\\y^2+12y+144=y^2+2\cdot y\cdot6+12^2-NOT\ (6^2\neq12^2)\\\\B.\ y^2+20y+100=y^2+2\cdot2\cdot y\cdot10+10^2-YES\\\\C.\ y^2-16y+64=y^2-2\cdot y\cdot8+8^2-YES\\\\D.\ y^2+10y+25=y^2+2\cdot y\cdot5+5^2-YES[/tex]
[tex]Answer:\ A.\ 144+12y+y^2[/tex]
