Straightedge-only construction of segment of length $\sqrt{7}$, given regular hexagon with unit sides

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Let's consider a regular hexagon with unit side length. Draw a line segment of length $\sqrt{7}$ using nothing except a straightedge (that is, an unmarked ruler). The position of the segment may be chosen as you wish.

My thoughts: I've drawn all sorts of lines and tried to get the segment in one of the inside triangles, but to no avail.

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The rectangle that has as basis a diagonal of the hexagon and as height the orthogonal median ( joining mean points of opposite sides) has diagonal = $\sqrt 7$.

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Added after Blue comment. enter image description here

All lines can be drown with an unmarked straightedge.

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Here's a variation on @Emilio's answer:

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Extend two hexagon edges to get $A$; then connect $A$ to $B$.