Archive
Special Issues Volume 4, Issue 5, October 2018, Page: 40-44
Modification Cross’ Theorem on Triangle with Congruence
M. Rusdi Syawaludin, Department of Mathematics, University of Riau, Pekanbaru, Indonesia
Sri Gemawati, Department of Mathematics, University of Riau, Pekanbaru, Indonesia
Received: Dec. 29, 2018;       Accepted: Jan. 15, 2019;       Published: Feb. 18, 2019
Abstract
Cross’ theorem states if any triangle ABC, on each side constructed a square and vertices of the square are connected, it will form another triangle which has an equal area to triangle ABC. In this paper we will discuss the modification Cross’ theorem on triangle, which is to construct a square outcase direction on each side triangle produced by Cross’ theorem. The purpose of this paper is to modify Cross’ theorem and give simple proof even junior or senior high school can answer. The process of proof is done in simple way, that is using a congruence approach. The result obtained are square vertices that are connected is form a trapezoid and have area 5 times the area of triangle ABC.
Keywords
Triangle, Square, Congruence, Cross’ Theorem
M. Rusdi Syawaludin, Mashadi Mashadi, Sri Gemawati, Modification Cross’ Theorem on Triangle with Congruence, International Journal of Theoretical and Applied Mathematics. Vol. 4, No. 5, 2018, pp. 40-44. doi: 10.11648/j.ijtam.20180405.11
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