Chapter 6 - Polygons and Quadrilaterals - 6-4 Properties of Rhombuses, Rectangles, and Squares - Practice and Problem-Solving Exercises - Page 382: 61

Yes, the quadrilateral shown is a parallelogram. We can see from the diagram that diagonal $\overline{AC}$ bisects diagonal $\overline{BD}$, and diagonal $\overline{BD}$ bisects diagonal $\overline{AC}$. In a parallelogram, diagonals bisect one another; therefore, we can conclude that $ABCD$ is a parallelogram.

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