Idiot\'s Guides Basic Math and Pre-Algebra

318 Appendix A

10. m’GAL =
    56 82
    2

  69  and

m’PAL = 180 – 69 = 111.

11. m’APE =^1
    2

220 140^1

2

  80 40 

12. m’FAT =^1
    2
    52 12^1
    2

 40  20 

13. ’RAC intercepts an arc of 360 – 72 = 288r.

m’RAC =^1

2

(288) = 144r.

14. Let x = the measure of arc QR.


15. m’P =^1
    2

2

2

xx x, but 2x + x = 360,

so x = 120 and m’P = 60r.

16. The area of a circle with a radius of 9 cm is
    81 S cm^2.


17. The circumference of a circle with a
    diameter of 12 inches is 12S inches.


18. The area of a circle with a diameter of
    32 cm is 16^2 S = 256S cm^2.


19. The radius of a circle with an area of
    36 S square meters is 6 meters, its diameter
    is 12 meters, and its circumference is
    12 S meters.


20. The diameter of a circle with a circumfer-
    ence of 24S feet is 24 feet, its radius is
    12 feet, and its area is 144S square feet.


21. The equation of a circle with its center at the
    origin and a radius of 3 units is x^2 + y^2 = 9.

m P QS QR

x

x

x

1

2

15 1

2

160

30 160

130

5

5

5

5

2

2

2

8

8

22.

23. The center of the circle (x – 8)^2 + (x – 3)^2 =
    49 is the point (8,3) and radius is 7.


24. The equation of a circle with center (4,9)
    and radius of 2 units is (x – 4)^2 + (y – 9)^2 = 4


25. 
    

Circle of radius 6 centered at (8,3)

-6 -2 062

-2

2

4

6

-4

-6

-8-9 -7 -5-4 -1-3 1345 789

-8

-9

-1

-3

-5

-7

8

9

1

3

5

7

-10 10

-10

10

y

x

-2 062

-2

2

4

6

-4

-6

-5-4 -1-3 134 5 789

-8

-9

-1

-3

-5

-7

8

9

1

3

5

7

10 11 12 13 14 15

-10

10

y

x