5. The functions \(f\) and \(g\) are defined by
$$\begin{aligned}
& \mathrm { f } : x \alpha \quad | x - a | + a , x \in \mathbb { R }
& \mathrm {~g} : x \alpha \quad 4 x + a , \quad x \in \mathbb { R }
\end{aligned}$$
where \(a\) is a positive constant.
- On the same diagram, sketch the graphs of f and g , showing clearly the coordinates of any points at which your graphs meet the axes.
- Use algebra to find, in terms of \(a\), the coordinates of the point at which the graphs of f and g intersect.
- Find an expression for \(\mathrm { fg } ( x )\).
- Solve, for \(x\) in terms of \(a\), the equation
$$\mathrm { fg } ( x ) = 3 a$$
\section*{6.}