The diagram shows the graph of \(y=h(x)\), where

\(h(x)=(x+a)^2(b+cx)\)

and \(a\), \(b\) and \(c\) are integers. The curve meets the \(x\)-axis at the points \((-2,0)\) and \((1.5,0)\), and the \(y\)-axis at the point \((0,12)\).

(a) Find the values of \(a\), \(b\) and \(c\).

(b) Use the graph to solve the inequality \(h(x)\leq9\).