Find the values of a and k from the curve 
The diagram below shows a curve with equation of the form ${y = kx(x +
 a)^2}$, which passes through the points (-2, 0), (0, 0) and (1, 3).



What are the values of a and k.

I know my roots are x = -2, x = 0 and x = 3.
But as the y intercept is 0, I don't see how I can get any meaningful values for k:
${k(x + 2)(x - 3) = 0}$
How can I find the values of k and a?

Observe that there is a double root at $-2$ since the curve is tangent to the x-axis and a single root at the origin. To find $k$ plug in the point $(1,3)$ and solve for $k$.
