Unit+2+Solutions

=Hints:= (scroll down for solutions)

1. A rectangle has opposite sides congruent. If you know one side is 16, then the opposite side is 16. The perimeter is how far around. Use that to find out how much the other two sides must be, then divide.

2. Two ways: Find smaller shapes and add (one rectangle, two squares) OR Find larger shape and subtract smaller shape (large rectangle, small square)

3. Draw a picture. The rectangle pool is inside the rectangle yard. Find the larger shape area, subtract the smaller shape area.

4. You know the dimensions of the room. You also know the carpet is 2 ft away from each side. Find the dimensions of the rug by subtracting off the distance away from the rug. Then find the area of the rug using rectangle area formula.

5. The height is at a right angle to the base.

6. count the squares.

7. The height is at a right angle to the base.

8. The height is at a right angle to the base.

9. A = 0.5 a p a is apothem the distance from the center to the midpoint of a side. p is the perimeter (how far around)

10. Similar to 9 but you know the area and you have to rearrange the equation to solve for a.

11. Find the area of the square, subtract the area of the circle four times. (all circles have the same area in this problem)

12. Solve circumference for radius, then use the radius to find area.

13. Write the equation for area of a circle equal to 441 pi, then rearrange and solve for r.

14. Area of an annulus. The small radius is the radius of the hot tub, the large radius is the small radius plus the 1.7 more.

15. Find the triangle, subtract out the circle area.

16. Write the equation for area of a trapezoid. Fill in all known information, then solve for b by rearranging.

17. Split into shapes and then add the areas of the smaller shapes.

18. Area of a segment. Find area of a sector and subtract area of a triangle.

19. Every time the rope hits a corner and bends there is a new radius.

=Solutions=

1. 224 cm squared 2. 230 m squared 3. 2799 m squared 4. C 5. 7.2 cm squared 6. 20 square units 7. 78 yd squared 8. 260 m squared 9. 165.6 in squared 10. 3.5 cm 11. (256 - 64pi) in squared 12. 169 pi cm squared 13. A 14. 37.9 m squared 15. (575 - 81 pi) cm squared 16. 45 cm 17. 46.5 cm squared 18. (25/4 pi - 25/2) cm squared 19. a. Area = 0.5 pi (20*20) + 0.25 pi (10*10) + 0.25 pi (10 *10) = 250 pi ft squared

b. Area = 0.5 pi (20*20) + 0.25 pi (17*17) + 0.25 pi (5 *5) + 0.25 pi (3*3) = 280.75 pi ft squared

c. 0.5 pi (20*20) + 0.25 pi (15*15) + 0.25 pi (13 *13) = 298.5 pi ft squared