# How to highlight the area between four lines in julia Plots.jl

**URL:** <https://discourse.julialang.org/t/how-to-highlight-the-area-between-four-lines-in-julia-plots-jl/84433>\
**Category:** Visualization\
**Tags:** plots\
**Created:** [July 18, 2022, 11:42pm UTC](https://discourse.julialang.org/t/how-to-highlight-the-area-between-four-lines-in-julia-plots-jl/84433 "2022-07-18T23:42:40Z")\
**Posts on this page:** 3\
**Page:** 1

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**Author:** ![Alex\_ricci](https://avatars.discourse-cdn.com/v4/letter/a/a4c791/32.png) [@Alex\_ricci](https://discourse.julialang.org/u/Alex_ricci)\
**Post date:** [July 18, 2022, 11:42pm UTC](https://discourse.julialang.org/t/how-to-highlight-the-area-between-four-lines-in-julia-plots-jl/84433/1 "2022-07-18T23:42:40Z")

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I want to visualize a simple optimization problem.  
The problem is:  
min 3x + 2y  
s.t. -3x + 3y \<= 5  
2x + 3y \>= 9  
x, y \>= 0  
How it is possible to highlight the feasible region in this problem. In other words, I want to highlight the area between -3x + 3y \<= 5, 2x + 3y \>= 9, x \>= 0 , y \>= 0

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**Author:** ![gdalle](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/gdalle/32/27854_2.png) [@gdalle](https://discourse.julialang.org/u/gdalle)\
**Post date:** [July 19, 2022, 4:51am UTC](https://discourse.julialang.org/t/how-to-highlight-the-area-between-four-lines-in-julia-plots-jl/84433/2 "2022-07-19T04:51:01Z")

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The easiest way might be [GitHub - JuliaPolyhedra/Polyhedra.jl: Polyhedral Computation Interface](https://github.com/JuliaPolyhedra/Polyhedra.jl)

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**Author:** ![rafael.guerra](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/rafael.guerra/32/216610_2.png) [@rafael.guerra](https://discourse.julialang.org/u/rafael.guerra)\
**Post date:** [July 19, 2022, 5:41am UTC](https://discourse.julialang.org/t/how-to-highlight-the-area-between-four-lines-in-julia-plots-jl/84433/3 "2022-07-19T05:41:16Z")

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Linking to a possible solution in this [other post](https://discourse.julialang.org/t/how-avoid-this-warning-when-i-use-contour/61327/18).