Question

Which of the following is not a parallelogram?
(a) Rhombus
(b) Rectangle
(c) Trapezium
(d) Square.

Answer 1

Hint: Try to remember the properties of each of the mentioned figures like the square is a parallelogram with all sides equal and all interior angles equal to $90^o$ . Once you are able to recollect the definitions of each figure, use the definitions to reach an answer. Drawing the figures might be very helpful.

Complete step-by-step answer:
Let us try to remember the definitions of all the figures mentioned one by one. First let us start with Rhombus. So, rhombus is a parallelogram with all its sides equal and diagonals perpendicular to each other.

Now, a rectangle is a parallelogram with each of the interior angles measuring $90^o$ while squares are the parallelograms with all the properties of a rectangle along with the constraint that all its sides must be equal.

Finally, a trapezium is a quadrilateral with one pair of opposite sides parallel and another pair of opposite sides is non-parallel.

So, from the above definitions it is clear that trapezium is not a parallelogram, as for being a parallelogram each pair of opposite sides must be equal and parallel.
Hence, the answer to the above question is option (c).

Note: Remember that square, rectangle and rhombus are parallelograms while kite and trapezium are not. Also, it is important to remember the properties of the mentioned standard quadrilaterals, as they are used very often. Also, be very clear about the definitions and don’t mix up their properties because they sound very similar and confusing.