hi abhishek.ciindore
Welcome to the forum.
If the equation has the form
then you can make three equations by substituting for (x,y) as follows:
(i) (0,0) (ii) (1,2) (iii) (6,0)
That should be enough to work out a, b, and c.
Check by substituting each 'x' value into your finished equation to see if it gives the right 'y'.
Bob