All of these would be perfectly fine represented by a pie chart except A, which doesn't add to 100%.
The question seems to be getting at the idea that a pie chart might be better when the slices are all visually different sizes. I don't really think that's right; a pie chart for D say, where the two slices are about the same, gives the correct impression of the relative frequencies, which are about the same.
Answer they're looking for: C
Answer: 6
Step-by-step explanation:
Slope is found by doing:

(x1 and y1 must be from the same ordered pair and x and y must be from the same ordered pair, however point (x1,y1) and (x,y) can be used interchangeably)
Let us say that (x1,y1) is (3,18)
And (x,y) is (5,30)

Answer:
0.05
Explanation:
Let x = the number
.05 = .1x
5/100 = (1/10)x Multiply both sides by 10.
5/10 = x
1/2 = x
Step-by-step explanation:
You're asking why

let's transpose the first equation for y
-2x-6y=18
-6y=18+2x
6y=-18-2x
y=-18/6-2x/6
y=-3-⅓x as required