Prove that the following sets of three lines are concurrent: `x/a+y/b=1, x/b+y/a=1\ a n d\ y=x`

Explanation

Given lines,`x/a+y/b=1, x/b+y/a=1\ a n d\ y=x`

Now, consider the following determinant:`|[b,a,-ab],[a,b,-ab],[1,-1,0]|`



`= b xx ab - a xx ab – ab xx (-a – b) = 0`


Hence proved, the given lines are concurrent.