All the angles of a quadrilateral are equal. What special name is given to this quadrilateral?
Let all the angles be equal to x
We know that,
Sum of all angles of a quadrilateral = 360°
⇒ x + x + x + x = 360°
⇒ 4x = 360°
⇒ x = 90°
Hence, the quadrilateral is a rectangle.