We have,
Equation of line
ax+3y−a=0......(1)
6x+ay−6=0......(2)
Comparing that,
a1x+b1y+c` 1=0
a2x+b2y+c2=0
Then,
a1=a
b1=3
c1=−a
a2=6
b2=a
c2=−6
Its many infinite many solutions
a1a2=b1b2=c1c2
⇒a6=3a=−a−6
⇒a6=3a=a6
We have,
a6=3a
a2=18
a=±√18
a=±√3×3×2
a=±3√2