Modification of the Cross Theorem on Non-Convex Quadrilateral

  IJMTT-book-cover
 
International Journal of Mathematics Trends and Technology (IJMTT)
 
© 2022 by IJMTT Journal
Volume-68 Issue-7
Year of Publication : 2022
Authors : Saniyah, Mashadi, Sri Gemawati
 10.14445/22315373/IJMTT-V68I7P507

How to Cite?

Saniyah, Mashadi, Sri Gemawati, "Modification of the Cross Theorem on Non-Convex Quadrilateral," International Journal of Mathematics Trends and Technology, vol. 68, no. 7, pp. 43-51, 2022. Crossref, https://doi.org/10.14445/22315373/IJMTT-V68I7P507

Abstract
This article discusses the modification of the Cross Theorem on a non-convex quadrilateral by expanding the outward square twice, thus forming four new two-dimentional figure. The proof is done using the sine and cosine rules. The result obtained is that the difference in the area of the two-dimentional figure that faces each other obtained from the Cross Theorem on a non-convex quadrilateral is equal to four times the area of the original quadrilateral.

Keywords : Non-Convex, Sine and Cosine, Cross Theorem.

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