The diagram shows the curve with equation \(y = 5x^4 + ax^3 + bx\), where \(a\) and \(b\) are integers. The curve has a minimum at the point \(P\) where \(x = 2\).
\includegraphics{figure_1}
The shaded region is enclosed by the curve, the \(x\)-axis and the line \(x = 2\).
Given that the area of the shaded region is 48 units\(^2\), determine the \(y\)-coordinate of \(P\).
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