Question

A quadrilateral has exactly 3 congruent sides Davis claims that the figure must be a rectangle why is his claim incorrect.

Answer 1

Check the picture below.

a rectangle is a quadrilateral, so is a rhombus and a parallelogram as well, however, a rectangle has 4 right-angles, a rhombus or parallelogram do not have to have right-angles, but all sides may be congruent.