Question

***********I NEED HELP PLEASE*********** For problems 1 and 2, graph the data points. Draw the line of best fit and, using complete sentences, explain how you found it in 3-4 sentences. Write the equation for the line of best fit in standard form.

(10, 150) (20, 275) (30, 340) (40, 400) (50, 475)

Title: Intersection Cars
Horizontal axis: Minutes elapsed
Vertical axis: Total cars passing through

Answer 1

if this is a regression line ...

Answer 2

your anchor point is you avgX and avgY values

y = m(x-avgX) + avgY for starters

Answer 3

I am not sure it is line of best fit

Answer 4

it is rising but i dont know how to solve it

Answer 5

this is algebra 2

Answer 6

m is a variance measure that I can never quite recall since it looks very similar to another setup ...

\[m=\frac{n\sum(xy)-\sum(x)\sum(y)}{n\sum(xx)-\sum(x)\sum(x)}\]
that might be it but id have to double check my text

Answer 7

there are a few best fit methods, the one im considering for this is called least squares method

Answer 8

i need an easier more simpler way? is that possible

Answer 9

not without knowing what approach they want you to take for a "best fit"

Answer 10

the good news is a recalled the correct setup for the slope :)

Answer 11

the high-low method is to take the line between the first and last points; but thats a rough estimate that is not really a "best fit" in general

Answer 12

can you use excel?

Answer 13

So then how do I solve it using the least squares method

Answer 14

yes

Answer 15

then the simplest thing to do is to use excel :) it has a trend line capability

Answer 16

how do i use this trend line you speak of?

Answer 17

plug in the point values as I did, insert a chart, scatterplot; then layout the trendline options

Answer 18

Wow you are a life saver thank you so much

Answer 19

it was either that or fight thru the "by hand" method

excel would make that a little simpler as well; its just a matter of defining the correct parts to construct the line with is all

Answer 20

how do i layout the trend line options?

Answer 21

after youve inserted the "scatter" chart, you get a green tab with a "layout" option in it.

inside of the layout option is a tab towards the middle rightish that says trendline

click the bottom to view more options and make sure the "show equation" is set.

Answer 22

i assume youve already chosen the data for the chart

Answer 23

I LOVE YOU SO MUCH

Answer 24

THANK YOU

Answer 25

lol, youre welcome :)