Question

Please help with archery question?

Answer 1

Archers need to use arrows that do not bend easily. Th e table shows how the weight of
an arrow aff ects its spine, or the distance the center of the arrow bends when a certain
constant weight is attached. Graph the data in the table to fi nd a linear and a quadratic
model for the data. Use the regression feature on your calculator to fi nd each model.
Which model is a better fi t? Explain

Answer 2

Weight (in grams)140 150 170 175 205
Weight (in inches) 1.4 1.25 0.93 0.78 0.43

Answer 3

ok... do you have a graphing calculator like a Ti 83 or Ti 84..?

Answer 4

no i dont

Answer 5

So how could i do this?

Answer 6

ummm well the question appears to have been written for a graphing calculator

well you could graph the data and find the line of best fit, thats really the easiest way of you don'g have a graphics calculator. Good luck

Answer 7

you cant help?

Answer 8

well you'll need to plot the ordered pairs, and then draw a line that best fits the data.

Once you have the line, find the slope and the y-intercept...

that will be the linear regression line.

The quadratic regression line is more difficult

Answer 9

my only suggestion is to use excel spreadsheet

Answer 10

okay thanks! so i should graph
Weight (in grams)140 150 170 175 205
Weight (in inches) 1.4 1.25 0.93 0.78 0.43

Answer 11

and find the line of best fit?

Answer 12

yep.... so if you have excel

have 2 columns,

use you heading with the data and put each set of data into a column next to each other.

can you do that..?

Answer 13

Yes

Answer 14

let me know when you have don it

Answer 15

k i will

Answer 16

Did it

Answer 17

ok... so you'll need to create a scatter plot.. so drag across the data to highlight it.

then go to the menu bar and click on Insert

Answer 18

when you have the Insert ribbon

select Scatter from the chart options..

Answer 19

Yup, and i pressed marked plot

Answer 20

well scatter with only markers, right?

Answer 21

just select the 1st choice... which is just points and no joining lines

Answer 22

Yes thats what i have

Answer 23

ok... so the graph is showing..?

just right click on one of the data points in the graph

Answer 24

you should see a list of choices

you want Add Trendline

Answer 25

Ok

Answer 26

How do you do that?

Answer 27

ok... so you have some blue points on the graph... just click on 1 and then all will appear with a little box around them

Answer 28

then if you move the mouse to 1 of the points and right click you get a list of options

Answer 29

It wont work, not doing that

Answer 30

i try to right click it, it just highlights the graph

Answer 31

umm hold on

Answer 32

ok... can you just try to right click on 1 point on the scatter graph and see if you get a menu..?

Answer 33

no, just highlights the graph

Answer 34

ok... so when you highlight the graph do you get a Design option on the ribbon at the top..?

Answer 35

specifically chart layout

Answer 36

yes i do

Answer 37

great in the chart layout... just scroll down and there is one that has a small fx on the layout option. this should given the linear regression

Answer 38

just click on the layout with the fx option.

Answer 39

i did that

Answer 40

ok... now the graph should display an equation... is that correct...?

Answer 41

the equation will be the linear regression equation for the data.

Answer 42

where should the equation be?? i dont see one, but the fx button is highlighted still

Answer 43

you version must be different to mine... I'd click the fx button and see what you get

Answer 44

i am using the skydrive version of microsoft excel

Answer 45

when i click on the numbers in the column, and press fx, it says insert a function

Answer 46

ok....

did it show the line...?

Answer 47

if the line is shown on the graph, try clicking on the line and see of you get an options box appear...

Answer 48

no, but the dots aligned in a straight row

Answer 49

ok... can you try the right click..on the line...?

Answer 50

okay

Answer 51

I have attached my 2 graphs with regression lines and equations...

Answer 52

thanks