Modification of the Cross Theorem on NonConvex Quadrilateral

International Journal of Mathematics Trends and Technology (IJMTT)  
© 2022 by IJMTT Journal  
Volume68 Issue7  
Year of Publication : 2022  
Authors : Saniyah, Mashadi, Sri Gemawati 

10.14445/22315373/IJMTTV68I7P507 
How to Cite?
Saniyah, Mashadi, Sri Gemawati, "Modification of the Cross Theorem on NonConvex Quadrilateral," International Journal of Mathematics Trends and Technology, vol. 68, no. 7, pp. 4351, 2022. Crossref, https://doi.org/10.14445/22315373/IJMTTV68I7P507
Abstract
This article discusses the modification of the Cross Theorem on a nonconvex quadrilateral by expanding the outward square twice, thus forming four new twodimentional figure. The proof is done using the sine and cosine rules. The result obtained is that the difference in the area of the twodimentional figure that faces each other obtained from the Cross Theorem on a nonconvex quadrilateral is equal to four times the area of the original quadrilateral.
Keywords : NonConvex, Sine and Cosine, Cross Theorem.
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