Question

If three angles of a quadrilateral are equal to 90° each, then the quadrilateral is a ______.

Options

• rectangle

• square

• parallelogram

• rhombus

Answer 1

If three angles of a quadrilateral are equal to 90° each, then the quadrilateral is a rectangle.

Explanation:

The sum of all four interior angles of a quadrilateral is 360°. Since three of the angles measure 90° each, the fourth angle is 360° − (90° + 90° + 90°) = 360° − 270° = 90°. Because all four interior angles are right angles (90°), the quadrilateral is a rectangle.