Question

The total number of degrees, D, in an n-sided polygon is given by the formula D=180(n-2). When Janelle solves for n, she gets n=D+360/180. Sophie solved the same equation for n and got an equivalent equation. Which of the following could be Sophie’s equation?

n=D/180 +2

n=D/180 -2

n=D-178

n=D-182

Answer 1

n=D/180 +2

Explanation:

Answer 2

The aim is to write n in one side of the equality:

1.D=180(n-2).

2. D=180n-360

3. D+360=180n

4. 180n=D+360

5.
`n= (D+360)/(180)= (D)/(180)+ (360)/(180)= (D)/(180)+ 2`