1. Area of a rectangle: A = bh This formula can be used for squares and parallelograms. b h

2. Area of a parallelogram: A = bh A base of a parallelogram is any of its sides. The corresponding altitude is a segment perpendicular to the base, drawn from the opposite side. The height is the length of the altitude. b h

3. Sample Problems Find the area of each figure. Round your answers to the nearest tenth.

4. Sample Problems Find the value of h in each parallelogram.

5. Sample Problems What is the area of with vertices A(-4, -6), B(6, -6), C(-1,5) and D(9, 5)? y x

6. Area of a triangle: A = ½ bh A base of a triangle is any of its sides. The corresponding height is the length of the altitude to the base. b h

7. Sample Problems Find the area of each triangle. Round your answers to the nearest tenth.

8. Area of a trapezoid: A = ½ h(b 1 + b 2 ) b2b2 h b1b1

9. Sample Problems Find the area of each trapezoid. If your answer is not an integer, round to the nearest tenth.

10. Area of a rhombus or kite: A = ½ d 1 d 2 d2d2 d1d1

11. Sample Problems Find the area of each rhombus. If your answer is not an integer, round to the nearest tenth.

12. Vocabulary Radius: The distance from the center to a vertex. Apothem: The perpendicular distance from the center to a side. Center Radius Apothem Central Angle 360 n

13. Apothem Area of a Regular Polygon A = ½ ap a = apothem P = perimeter

14. Sample Problems Find the area of each regular polygon. If your answer is not an integer, round to the nearest tenth. 1.equilateral triangle with side length of 16 ft 2. regular octagon with side length of 11.6 cm and apothem of 14 cm

15. Sample Problems Find the area of each regular polygon. If your answer is not an integer, round to the nearest tenth. 3. an octagonal floor of a gazebo with apothem 6 ft 4. a square deck with radius 2 m

16. Theorem 10-7: Perimeters and Areas of Similar Figures If the similarity ratio of two similar figures is 1) the ratio of their perimeters is 2) the ratio of their areas is abab abab a2b2a2b2

17. Sample Problems For each pair of similar figures, find the ratio of the area of the first figure to the area of the second.

18. Sample Problems For each pair of similar figures, the area of the smaller figure is given. Find the area of the larger figure.