A convex quadrilateral is a four-sided polygon where all interior angles are less than \(180^\circ\), and each vertex points outward. These quadrilaterals have no indentations, meaning the diagonals lie entirely within the shape. Convex quadrilaterals are a broad category that includes rectangles, squares, trapezoids, and rhombuses.
The area of a convex quadrilateral can be calculated if two adjacent sides and the included angle are known:
\[ A = \frac{1}{2} ab \sin(\alpha) \]
where: