Parallelograms and their Properties
Parallelograms and their Properties: Overview
This topic covers concepts such as Elements of a Parallelogram, Sufficient Condition for a Quadrilateral to be a Parallelogram, Properties of a Parallelogram, Properties for Sides of a Parallelogram, Properties for Angles of a Parallelogram, etc.
Important Questions on Parallelograms and their Properties
If quadrilateral is a parallelogram, with diagonal , find the length of (in )?
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Find the value of (in degrees) for the quadrilateral to be a parallelogram?
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Find the value of , for parallelogram
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In a quadrilateral , diagonal and bisect each other at point . The quadrilateral is a _____
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In a quadrilateral , and . The quadrilateral is a _____
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Two adjacent angles of a parallelogram are and The value of is
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The opposite angles of a parallelogram are of equal measure.
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If one of the angles of a parallelogram is , then the value of opposite angle is
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In and and Vertices and are joined to vertices and respectively. Then, the quadrilateral is a parallelogram.
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is a parallelogram in which and side is produced to point as shown in the figure. If then find .
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The lengths of the diagonals of a rhombus are and respectively. If the length of each side of the rhombus is , find the value of .
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In a quadrilateral , opposite angles are equal. If , and , then find the value of .
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In the adjoining figure, is a parallelogram in which and . If , find the value of .
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In the adjoining figure, is a parallelogram in which and If , then find the value of .
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Which of the following is true for a parallelogram?
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Consider a parallelogram ABCD. Fill the blanks to find the type of parallelogram obtained if the diagonals of the parallelogram are equal.
In ∆ ABC and ∆ ABD,
AB is the common side.
AC = BD (Diagonals are equal)
AD = BC (Opposite sides of a parallelogram are equal)
∴ By SSS rule of congruency, the ∆ ABC and ∆ ABD are congruent.
∠ DAB = ∠ CBA (By CPCT)
Similarly,
∠ CDA = ∠ DCB
But ∠ DAB + ∠ CBA = 180 degrees (Co interior angles of parallel lines are supplementary)
∴ ABCD is a _____.
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Jaya had a set of 6 identical matchsticks and was trying to make a parallelogram with them. If one matchstick represents one side of the parallelogram, then, with how many matchsticks could she make the parallelogram?
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The diagonals of a quadrilateral bisect each other. Prove that this quadrilateral is parallelogram.
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In a parallelogram, adjacent angles are equal.
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In a _____ opposite sides are equal, opposite angles are equal and diagonals bisect one another (Parallelogram/Trapezium/Kite/Arrowhead).
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