If three of the angles of a quadrilateral are right angles, then the fourth angle must also be a right angle.
The sum of the interior angles of any two-dimensional (planar) geometric figure must add up to 360 degrees. As this is the case, three times 90 equals 270, and 270 subtracted from 360 leaves 90.
The quadrilateral described here is a rectangle. If all the sides are the same length, it is a special case of a rectangle that we call a square.
A square
Any parallelogram, including rhombus, but not including rectangle or square.
rectangle
i have a feeling its a rhombus
A square. Its opposite sides are equal and it has 4 right angles.
square
Rhombus!
a pentagon
rhombus. The rhombus is a quadrilateral with all sides equal in length. It is also a parallelogram, so opposite sides are parallel and equal in length, and opposite angles are equal.
a rhombus
A Rectangle.
A square
a square
Any parallelogram, including rhombus, but not including rectangle or square.
rectangle
Opposite sides are of equal length and parallel. The four angles are all right-angles (90 degrees( .
A parallelogram always has opposite sides of equal length. Its 4 angles may be right angles, but in most parallelograms they're not. If they are, then that parallelogram is also called a 'rectangle'.