Question

the cost of printing a store flyer is 440 for 1000 copies and 880 for 2000 copies. write a linear equation for modeling this data.

Answer 1

Since they tell us that this is linear, having a constant rate of change, we can express this as a line:

y=mx+b, where m=slope (change in y divided by change in x) and b=y-intercept (value of y when x=0)

First find the slope, or m, which mathematically is:

m=(y2-y1)/(x2-x1), in this case:

m=(880-440)/(2000-1000)

m=440/1000

m=0.44, so far our line is:

y=0.44x+b, now we can use either data point to solve for b, I'll use (1000,440)

440=0.44(1000)+b

440=440+b

0=b, so our line is just:

y=0.44x

Answer 2

(1000,440)(2000,880)
slope = (880 - 440) / (2000 - 1000) = 440/1000 = 0.44

y = mx + b
slope(m) = 0.44
(1000,440)...x = 1000 and y = 440
sub and find b, the y int
440 = 0.44(1000) + b
440 = 440 + b
440 - 440 = b
0 = b

so ur equation is : y = 0.44x