1) a^2+ 2/7a+1/49
2)1/81+2/9a+a^2
3) n^2/16+mn/6+m^2/9
4)k^2/4-kt/5+t^2/25
5) 169/9-26/3x+x^2
6) y^2+13/2y+169/16
7) z^2-52/5z+676/25
8)81/4+9t+t^2
