Problem 5
Answer: Yes the points are coplanar
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Step-by-step explanation:
Note how all four points are in the same plane, aka face, along the top of the 3D block. The term "coplanar" simply means "all in the same plane", so that's why the points are coplanar.
In contrast, the set of points {H,J,K,Z} are not all coplanar because H,J,K are in the top plane, while Z is not.
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Problem 6
Answer: line segments WX, XY, and XK
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Step-by-step explanation:
All three lines mentioned above involve the letter X in some fashion. The order doesn't matter. Also, those lines intersect at the common point X.
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Problem 7
Answer: point W
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Step-by-step explanation:
The plane WXYZ is the bottom face, in which we can think of as the floor of the building. The segment HW is from the floor and goes up vertically. We can consider this to be like a pole beam of the structure. The plane and segment both have point W in common. Note that the letter "W" is found in the sequences WXYZ and HW, and it's the only common letter.
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Problem 8
Answer: The points are not collinear
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Step-by-step explanation:
To be collinear, the points must all be on the same straight line. We see that isn't the case with points W, X and Y.
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Problem 9
I'm not entirely sure what your teacher is asking here, so I would ask for a second opinion.