Editing Slope (section)

==Notation==
There seems to be no clear answer as to why the letter ''m'' is used for slope, but it first appears in English in [[Matthew O'Brien (mathematician)|O'Brien]] (1844)<ref>{{citation |last=O'Brien |first=M. |title=A Treatise on Plane Co-Ordinate Geometry or the Application of the Method of Co-Ordinates in the Solution of Problems in Plane Geometry |year=1844 |place=Cambridge, England |publisher=Deightons}}</ref> who introduced the equation of a line as {{nobreak|1="''y'' = ''mx'' + ''b''"}}, and it can also be found in [[Isaac Todhunter|Todhunter]] (1888)<ref>{{citation |last=Todhunter |first=I. |title=Treatise on Plane Co-Ordinate Geometry as Applied to the Straight Line and Conic Sections |year=1888 |place=London |publisher=Macmillan}}</ref> who wrote "''y'' = ''mx'' + ''c''".<ref>{{cite web |last=Weisstein |first=Eric W. |title=Slope |url=http://mathworld.wolfram.com/Slope.html |url-status=live |archive-url=https://web.archive.org/web/20161206182915/http://mathworld.wolfram.com/Slope.html |archive-date=6 December 2016 |access-date=30 October 2016 |publisher=MathWorld--A Wolfram Web Resource}}</ref>