For 10 aren't you getting by substituting v=10x+6y
And then integrating by half angle ???
I wanted a shorter method as it works be to long
You will get quadratic of dy/dx.
Then it can be done.
That quadratic itself I am unable to solve bro @pratyaksh_tyagi
I did a silly calculation error was getting a x only term in the root
Should have checked my calculations !