a2+x2−2ax−ax=0
(x−a)2=ax ..... (i)
ax2−2a2x+1=0 ..... (ii)
Divide this equation by a on both sides, we get
x2−2ax+1a=0
Add both sides a2, we get
x2−2ax+a2+1a=a2
(x−a)2=a2−1a
ax=a2−1a ........ From
x=a3−1a2
Substitute a in the equation a2+x2−3ax=0
We get on simplification
a6−a3=1