Find zero force members of a truss

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MienTommy
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I was wondering how members CL and JE are zero members? They both have forces applied to them, so why would it be zero? The attached image is the solution.
 
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  • Planar truss diagram with labelled joints A to J, pin support at A, roller support at G, and downward loads applied at C, D and J, with a load arrow shown on the left at C; the members are drawn as a Pratt-style truss with a bottom chord from A to G.
    20151008_014918.jpg
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Loads are applied to points C, D and J.

Load D is supported by the triangle DGA, that is by the straight chords alone.
The upper chord ABCDEFG is under compression, the lower GHJKLA is under tension.
Load J is supported by the triangles JDA and JDG.
Load C is supported by the triangles CKA, CKD and DKG.

Members BL, CL, EJ and FH have not been mentioned so they transfer no force with this loading.