Question

A picture is enlarged by keeping its width the same and increasing its length. The scatter plot shows the perimeter of the picture (y) for different lengths (x):
(graph on bottom of question)

Which function best represents the data in the scatter plot?

y = 2x − 20
y = 2x + 20
y = x − 20
y = x + 20

Answer 1

Answer: y = 2x + 20

Step-by-step explanation: slope, y2 - y1/x2 - x1

replace it with these numbers 120 - 60/50 - 20=60/30

than,simplified it we get 2/1. so, now we  have the slope of our equation

y = 2x + b. but we still have b (or where the y intersects.) now are slope we have to change it to 1/2 because we are going backwards. So multiply 60 by .5, Thus will give us 30

Now we have y = 2x + 30, But that's not one of your answer,

So y = 2x + 20 cant be -20 because this is a positive y intersect and We know it is a slope of 2.

Therefore the answer is : y = 2x + 20

ALSO I got it correct on the test!!