Question

Which of the following quadrilateral is not a rhombus?

• A. Diagonals bisect opposite angles
• B. All four sides are equal
• C. Diagonals bisect each other
• D. One angle between the diagonals is 60°

Answer 1

The correct option is D

One angle between the diagonals is 60°

Explanation for the correct option:

Option (d): One angle between the diagonals is 60°.

Rhombus: A rhombus has all four sides equal. Diagonals of the rhombus bisect opposite angles. Also, the diagonals bisect each other.

The diagonals of the rhombus bisect each at $90°$.

It means that the angle between the diagonals can not be $60°$.

Hence, the quadrilateral is not a rhombus.

Explanation for the incorrect option:

Option (a): Diagonals bisect opposite angles.

Yes, the diagonals of the rhombus bisect opposite angles.

Therefore, the quadrilateral is a rhombus.

Option (b): All four sides are equal.

A parallelogram with all sides equal is a rhombus.

Hence, the quadrilateral is a rhombus.

Option (c): Diagonals bisect each other.

When the diagonals of a quadrilateral bisect each other, it is a rhombus.

Hence, the quadrilateral is a rhombus.

Thus, option (d) is the correct option.