how do i differentiate 6x+10y.dy/dx-6+20d.dy/dx=0
Just in case a picture helps...
Top row is what you wrote, bottom row the derivative. Triangular network is the product rule.
Don't integrate - balloontegrate!
Balloon Calculus Forum
Edit: thanks for the thanks, but do refresh the page because I've just had to correct an error in the pic - sorry!