a 3 sided shape is a right angle triangle
a Pentagon is five sided and CAN have 3 right angles.
No because a 4 sided rectangle also has four right angles
test
A right trapezoid is a four-sided polygon with two right angles and two parallel sides.
no
A rhombus, an equal sided parallelogram or an equal sided quadrilateral with no right angles.
You can make a four sided shape with 3 right angles, but it must have another right angle, too. So technically, yes.
A right angled pentagon.
A right trapezium.
octogan
Hexagon