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Quadrilaterals
These shapes have four sides and 360° of interior angle goodness.
by
Vaibhav Raj
by
Trevor Arashiro
In the above diagram, quadrilateral \(ABCD\) is a parallelogram and \(M\) is the midpoint of \(\overline{DC}.\) If the area of \(\triangle BNC\) is \(42,\) what is the area of \(\triangle MNC?\)
by
Hemang Agarwal
In rectangle ABCD (below left), \(AB=3\) and \(BC=5\). The corner at C is folded up (below right) and lands on \(\overline{AB}\) so that \(AC=2\) and \(CB=1\).
The area of quadrilateral CPNM can be written as \(\frac{m}{n}\), where m and n are positive, coprime integers. Find \(m+n\).
by
Matt Enlow
What is the area of a rhombus of side 13 such that the sum of its two diagonals is 34?
by
Paola Ramírez