As we have to differentiate both x and y, we must use implict differentiation for the y by differentiating it with respect to x (also written as d/dx)
5x2 -> 10x (multiply the power by the number at the start and take away 1 from the power)
2y3 -> 6y2 . dy/dx (the dot means multiply)
8 -> 0 (a sole constant always differnetiates to 0)
17 -> 0
Therefore the equation now looks like this:
10x + 6y2 . dy/dx = 0
so 6y2 .dy/dx = -10x
so dy/dx = -10x / 6y2