The graph is a piecewise defined function.

Observe the graph.

A straight line exists in the interval \"0\\leq.

The end points of the straight line are \"(0, and \"(3,.

Standard form of line equation using the points \"(x_{1}, and \"(x_{2}, is \"(y-.

Substitute \"(x_{1}, and \"(x_{2}, in the line equation.

\"(y-

\"y-3=\\frac{-3}{3}(x)\"

\"y-3=-1(x)\"

\"y=-x+3\"

The equation of the line is \"f(x)=-x+3\" in the interval \"0\\leq.

Observe the graph.

A straight line exists in the interval \"3\\leq.

The end points of the straight line are \"(3, and \"(5,.

Standard form of line equation using the points \"(x_{1}, and \"(x_{2}, is \"(y-.

Substitute \"(x_{1}, and \"(x_{2}, in the line equation.

\"(y-

\"y=\\frac{4}{2}(x-3)\"

\"y=2(x-3)\"

\"y=2x-6\"

The equation of the line is \"f(x)=2x-6\" in the interval \"3\\leq.

Then the piecewise function is \"f(x)=\\left\\{\\begin{matrix}.

The function is \"f(x)=\\left\\{\\begin{matrix}.