# Filling between more than two boundaries

Here is a simple example of what I am trying to do; fill the area described by the three inequalities:

$$y \le 11 + x \label{1} \tag{1}$$ $$y \le 27 - x \tag{2}$$ $$y \le \frac{1}{5}(90 - 2x) \tag{3}$$

I have so far:

Plot[{11 + x, 27 - x, 1/5 (90 - 2 x)}, {x, 0, 20},
Filling -> {2 -> {{3}, {White, LightBlue}}}]


Which produces:

My question is how to add multiple constraints on an area in general -- so for this specific question add the constraint specified by equation $\eqref{1}$.

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• You could use your constraints to define a Region and then use RegionPlot to plot it, including a colored fill. Search this website for similar questions. – bbgodfrey Apr 1 '15 at 14:38

r = ImplicitRegion[

Plot[{11 + x, 27 - x, 1/5 (90 - 2 x), Min[11 + x, 27 - x],