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

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.

- "runner b is moving at a slower rate."

- "the graphs shown are graphs of distance(km) against time(min).

the slopes of this graphs are are given by:

slope = (change in y)/(change in x)

= (change in distance)/(change in time)

this is the formula for finding the speed. so, the slope of these graphs represent the speed of the runner.

taking each division in the graph to represent 1 on both axis:

runner a ⇒ speed = (2-0)/(1-0)

= 2/1

= 2 km/min

runner b ⇒ speed = (3-0)/(3-0)

= 3/3

= 1 km/min

this shows that   runner b is moving at a slower rate."