When given an equation in parametric form, how can you figure out dy/dx?

Assuming we are given that x = f(t) and y = g(t), we first differentiate x with respect to t to obtain dx/dt. Then, we differentiate y with respect to t to obtain dy/dt. Much like fractions, we can find dt/dx by finding the inverse of dx/dt (by doing 1 divided by dx/dt).

Now that we know how to figure out dy/dt and dx/dt, again similarly to fractions we can multiply these together. Note how the "dt"s cancel out and we are left with dy/dt.