name the intersection of plane HEG and plain DFE
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we conclude that the intersection of the planes HEG and DFE is the line FE
Remember that the intersection of two planes is a line, so we just need to find a line that belongs to the two planes HEG (This plane would be the face that is behind the cube).
And the plane DFE is the right face of the shown cube.
Now, by looking at the given diagram, you can see that the line that belongs to two planes is the line EF (it is a common edge for the two faces that define the planes).
If you want to learn more about planes:
https://brainly.com/question/1655368
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