Difference between revisions of "Perpendicular lines"
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| − | '''Perpendicular lines''' are lines which intersect to form four [[right angles|90<sup>o</sup> angles]]. | + | '''Perpendicular lines''' are lines which intersect to form four [[right angles|90<sup>o</sup> angles]].<ref>''Merriam-Webster's Third International Dictionary''.</ref> In Euclid's ''Elements'', they were defined as lines which intersect to form one right angle,<ref>Euclid. ''The Elements''. Book I.</ref> and they were proven to form four via the [[Perpendicular Lines Theorem]]. |
| − | [[Category: | + | ==References== |
| + | {{Reflist}} | ||
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| + | [[Category:Plane Geometry]] | ||
Latest revision as of 02:56, August 3, 2017
Perpendicular lines are lines which intersect to form four 90o angles.[1] In Euclid's Elements, they were defined as lines which intersect to form one right angle,[2] and they were proven to form four via the Perpendicular Lines Theorem.