I really dont know how to do this and I need some help.

1. Radius = 4 cm

2. Diameter = 8 cm

4 x 2 = 8

3. Circumference = 25.12 cm

8 x 3.14 = 25.12

4. Area = 50.24 cm^2

3.14 x 4^2

3.14 x 16 = 50.24

5. Radius = 5 in

6. Diameter = 10 in

5 x 2 = 10

7. Circumference = 31.4 in

10 x 3.14 = 31.4

8. Area = 78.5 in^2

3.14 x 5^2

3.14 x 25 = 78.5

9. Radius = 8 mm

16/2 = 8

10. Diameter = 16 mm

11. Circumference = 50.24 mm

16 x 3.14 = 50.24

12. Area = 200.96 mm^2

3.14 x 8^2

3.14 x 64 = 200.96

13. Radius = 7.4 cm

14.8/2 = 7.4

14. Diameter = 14.8 cm

15. Circumference = 46.472 cm

14.8 x 3.14 = 46.472

16. Area = 178.1636 cm^2

3.14 x 7.4^2

3.14 x 56.74 = 178.1636

17. Area = 44 m^2

10 - 6 = 4

8 x 4 = 32

6 x 2 = 12

32 + 12 = 44

18. Area = 7.74 mm^2

6 x 6 = 36

6/2 = 3

3.14 x 3^2

3.14 x 9 = 28.26

36 - 28.26 = 7.74

answer: this is not a question

step-by-step explanation: this is a answer

starting with:    

5 + x - 12 = 2x - 7   

5 + x - 12 - x = 2x - 7 - x (subtract x from both sides)   

5 - 12 = x - 7 (combine and cancel x's from both sides)   

5 - 12 + 7 = x - 7 + 7 (add 7 to both sides)   

0 = x (add numbers together on both sides)       

so in order for the equation to be true, x must be 0.   

trying x = -0.5   

5 + x - 12 = 2x - 7 (original equation)   

5 + -0.5 - 12 = 2(-0.5) - 7 (plug in value of x)   

5 + -0.5 - 12 = -1 - 7 (did multiplication)   

-7.5 = -8 (did addition on both sides)       

since -7.5 is obviously not equal to -8, the value of -0.5 for x is wrong.   

trying x = 0   

5 + x - 12 = 2x - 7 (original equation)   

5 + 0 - 12 = 2(0) - 7 (plug in value of x)   

5 + 0 - 12 = 0 - 7 (did multiplication)   

-7 = -7 (did addition on both sides)       

since -7 equals -7, that demonstrates that the value of 0 for x is correct.   

trying x = 1   

5 + x - 12 = 2x - 7 (original equation)   

5 + 1 - 12 = 2(1) - 7 (plug in value of x)   

5 + 1 - 12 = 2 - 7 (did multiplication)   

-6 = -5 (did addition on both sides)       

since -6 is obviously not equal to -5, the value of 1 for x is wrong.