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If ab ∥ CD, CD ∥ EF, EF ∥ GH are known, what is the positional relationship between AB and GH, and explain the reason A——B C———D E————F G—————H
Parallel two lines parallel to the same line
Ab ∥ CD, EF ⊥ AB and CD have two points g and h on e, F, AB and CD, connecting GH. Given GH = EF, can we explain GH ⊥ AB and CD?
It's not a math problem, just a proof. The problem may not be very good, but the general meaning is like this
Because ab ∥ CD, EF ⊥ AB, Cd in E, F
So EF is the distance between AB and CD, and is the minimum distance between any two points on the two straight lines AB and CD
Because GH = EF, the distance between two lines is equal everywhere
So GH is also the distance between AB and CD
So GH ⊥ AB, CD
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