Question

What’s the name of that shape?

Answer 1

It’s a trapezoid

Explanation:

A trapezoid can have a flat side and can look normal.

Answer 2

trapezoid (U.S.A.)

trapezium (UK)

Explanation:

On the right side, two sides are perpendicular to the same side. That makes those two sides parallel. A quadrilateral with 2 parallel sides is a trapezoid (in the U.S.) or trapezium (in the UK.)