Group like numbers
6-3-4i-2i
3-6i

x is income in a given month = 930
u is average income = 900
SD is standard deviatio = 15
so z= (930-900) /15 =30/15 =2
answer 2
They are a distance of 2 away from each other
24 - 3 = 21 cookies given away.
For 7 friends that's 21/7 = 3 cookies each
Check by multiplying 3*7 = 21 cookies for friends. Adding his 3 cookies is 21+3=24 cookies, which is what he started with
The slope of a horizontal line is zero. It has a slope, but slope = 0 and this makes it different from a vertical line which has a slope that is undefined because you cannot divide 0 over 0 which is how much a vertical line rises and runs.