Hello, bherila!
Find the equation of the curve that goes through (1,3)
for which any tangent and the line from the origin to the point of contact
make with the ordinate a triangle having area . Code:

* * y = f(x)
 *
 * *
 * P(p,q)
 o /
 o /
 o /
B o /
 /
 /
 /
  *           
O

We have a function:
Let be a point on
is the segment from the origin to point
is the tangent at .
. . The slope of this tangent is and it contains
. . Its equation is: .
. . Its yintercept is: .
The base of is: .
The height of the triangle is: .
The area of
\. . which simplifies to: .
Divide by
Hence, we have: .
Integrating factor: .
So we have: .
Then: .
Integrate: .
Multiply by
Since is on the curve,
. .
Therefore: .