"alternate angles." YourDictionary, n.d. Web. 17 August 2018. <http://www.yourdictionary.com/alternate-angles>.
alternate angles. (n.d.). Retrieved August 17th, 2018, from http://www.yourdictionary.com/alternate-angles
(geometry) the internalangles made by two (parallel) lines with a third, on opposite sides of it.If the parallels AB, CD, are cut by the line EF, intersecting at points G and H, then the angles AGH, GHD, are called alternate angles (as also are the angles BGH and GHC).
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