Question

A group of students is trying to determine the number of cars that move along a certain section of roadway the dot plot below shows the speed of 20 vehicles Speed: 29 30 31 32 33 34 35 36 37 38 39 40

Answer 1

`y=x+28`

Explanation:

All coordinates are

(1,29); (2,30); (3,31); (4,32); (5,33); (6,34); (7,35); (8,36); (9,37); (10,38); (11,39); (12,40).

So, what we need to do is to find the line that best fit this data.

Now, notice that x-values and y-values both increase 1 unit, that means the constant ratio of change is 1, which is also defined as the slope of the line that bets fits.

Then, we need to use the point-slope formula and one point

`y-y_(1) =m(x-x_(1) )\\y-29=1(x-1)\\y=x-1+29\\y=x+28`

Where the y-intercept is at (0,28).