How many obtuse angles does a parallelogram have?

A parallelogram has one pair of obtuse angles.

Nov 24, 2015

Either two or none.

Explanation:

By definition a parallelogram is a quadrilateral whose opposite sides are parallel.
So a square or a rectangle is also a parallelogram.But they don't have any obtuse angles.

Aug 17, 2017

$2$ obtuse angles are opposite and equal.

Explanation:

The opposite angles in a parallelogram are equal.

The parallel sides also means that there are 4 pairs of co-interior angles which are supplementary, (add to 180°)

$2$ angles will always be obtuse and the other $2$ will always be acute.

As the parallelogram leans over, the obtuse angles get bigger and the acute angles get smaller.

When all the angles are equal, they will be 90° and the shape will be a rectangle.