# Supply/Demand Curve Equation (beginner) [duplicate]

The linear demand function is $$Q_D = a + b(P)$$. I understand from this thread that it can be thought of as a simplification/magnification of the overall demand curve.

Is there an equation that represents a demand curve such as the linear equation represents a linear curve?

Are students taught how to find the equation of the actual curve? (or why not) Almost every example I see is finding the linear function.