Question

Explain whether a rectangle is a convex quadrilateral or concave quadrilateral by giving reason?

Answer 1

A rectangle is a convex quadrilateral because each of its interior angle is less than 180°
A convex quadrilateral is a quadrilateral whose each interior angle is less than 180°

Answer 2

A quadrilateral is a plane figure that has four sides or edges, and also have four corners or vertices.

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