A Rectangle Is A Parallelogram With A Right Interior Angle

The word rectangle comes from.

A rectangle is a parallelogram with a right interior angle. In a parallelogram adjacent angles are supplementary that is their sum is 180 o. It can also be defined as an equiangular quadrilateral since equiangular means that all of its angles are equal. Because a rectangle has 4 equal interior right angles whereas a parallelogram does not have 4 equal interior angles but they are both in the same class as 4 sided quadrilaterals.

That s more than enough to make your parallelogram a rectangle. The term oblong is occasionally used to refer to a non square rectangle. Note for example that the angles abd and acd are always equal no matter what you do.

Therefore adjacent angle to the one that is equal to 90 o is measured 180 o 90 o 90 o that is it s also right angle. The properties of a rectangle 4 right angles. For proof refer to unizor menu items geometry quadrangles parallelogram.

Because the measures of the interior angles of a quadrilateral add up to 360º you can show that all four angles of our parallelogram are right angles. Because a rectangle has 4 equal interior right angles whereas a parallelogram does not have 4 equal interior angles but they are both in the same class as 4 sided quadrilaterals. Since there are two adjacent angles both are equal to 90 o.

A parallelogram however has some additional properties. Calculate the angle of a parallelogram if given 1 sides and diagonal 2 sides and area of a parallelogram. A parallelogram can be defined as a quadrilateral whose two s sides are parallel to each other and all the four angles at the vertices are not 90 degrees or right angles then the quadrilateral is called a parallelogram.

In euclidean plane geometry a rectangle is a quadrilateral with four right angles. Now since a rectangle is a parallelogram its opposite sides must be congruent and it must satisfy all other properties of parallelograms. The opposite sides of parallelogram are also equal in length.