Question

the scatter plot below shows the relationship between the number of video files (x) stored on a computer and the number of gigabytes (y) of storage space available on the computer.
based on the scatter plot, which equation represents a line of best fit that could be used to predict the number of gigabytes of storage space available on the computer based on the number of video files that could be stored on the computer?
a. y = -14x + 250
b. y = -9x + 116
c. y = -8x + 227
d. y = -4x + 189

Explanation:

Step1: Identify trend direction

The scatter plot shows a negative linear trend (y decreases as x increases), so the slope is negative (all options satisfy this).

Step2: Estimate y-intercept

When x=0 (no video files), y should be the initial storage. The first point is near x=2, y≈220. Test x=2 in options:
A: $y=-14(2)+250=222$
B: $y=-9(2)+116=98$ (too low)
C: $y=-8(2)+227=211$
D: $y=-4(2)+189=181$ (too low)

A and C are plausible; B and D are eliminated.

Step3: Check slope magnitude

The trend is moderate (not extremely steep). Slope of -14 (A) is too steep (e.g., x=10: $y=-140+250=110$, which is lower than most points at x=10). Slope of -8 (C): x=10 gives $y=-80+227=147$, which is close to the point at x=10 (≈130-140, reasonable).

Answer:

C. $y=-8x + 227$