Answer: The equation is differentiated implcitly, with respect to x and y
Step-by-step explanation: x2y - 8xy + 18y = 0
By implicit differentiation: 2y + 2xdy/dx - (8y + 8dy/dx) - 18dy/dx = 0
2y - 8y - 8dy/dx - 18dy/dx + 2xdy/dx = 0
-6y + 2xdy/dx - 26dy/dx = 0
2xdy/dx - 26dy/dx = 6y
dy/dx(2x - 26) = 6y
∴ dy/dx = 6y/2(x - 13) = 3y/(x - 13)