Class IX Mathematics
Chapter 8: Quadrilaterals
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Syllabus Sections
Key Formulas & Equations
Click Copy to duplicateMid point Theorem
DE = \frac{1}{2}BC \land DE \parallel BC
Line segment joining mid-points of two sides of a triangle is parallel to and half the length of the third side.
Related Formulas from Adjacent Chapters
Triangle Inequality
a + b > c
[From Triangles] Sum of lengths of any two sides of a triangle must exceed length of third side.