a2-3a=-1
a2=3a-1
2a5-5a4+2a3-8a2/a2+1=
-2a3+a4+2a3-8a2/a2+1
=a4-8a2/a2+1
=3a3-a2-8a2/a2+1
=3a3-9a2/a2+1
=9a2-3a-9a2/3a-1+1
=-3a/3a=-1
a2-3a=-1
a2=3a-1
2a5-5a4+2a3-8a2/a2+1=
-2a3+a4+2a3-8a2/a2+1
=a4-8a2/a2+1
=3a3-a2-8a2/a2+1
=3a3-9a2/a2+1
=9a2-3a-9a2/3a-1+1
=-3a/3a=-1