Worksheet, quiz, and solutions accompanying the video lesson Polygons & Circles Explained: From Pentagons to πr²Video Description: Learn the essentials of polygons and circles—names (pentagon → decagon), regular vs. irregular, the interior-angle sum (n−2)·180°, what π is, and the key circle formulas C = 2πr and A = πr². We also connect circumference to radian measure on the unit circle and solve a practical application: Will a 7-ft-radius parachute fit in a 12×12 room? More videos in this serie