# Linear Regression with Biological Data

- Author:
- A B Cron

This is an application take from the MathBits web site. Instructions for TI calculators are at the bottom. Full lesson.
The points were type in a spreadsheet (A,B).

- Use Move Tool move and your mouse to highlight the data in the spreadsheet on the right.
- Right-click on the highlighted area and select Create|List of points. You now have the data graphed.
- Use to Line Tool to manually draw a line of best fit.
- From this line you can find the slope of the line using the Slope Tool and click on the line.
- Use the Intersection Tool to find the y-intercept, right-click on point to show point and value. To look get the y-intercept, right-click on the point, select Object Properties and change the label option to name and value.
- Write the equation of the line, y = slope x + y-intercept.
- Enter your equation for y = mx + b here:
- To validate your solution, clear the applet with recycle recycle, repeat Step 1 and Step 2 followed by Step 9
- To check your manually drawn line, use the line of best fit tool bestFit to validate your solution.
- Click on Find f(x) button, compare result above to the f(x) on the GeoGebra screen.

Mathbits http://mathbits.com/Mathbits/TISection/Statistics2/linearREAL.htm
y = 3.244x + 26.012
This applet can be used by teachers in a demonstration mode in the classroom or teachers can have students load it on their own computers as a worksheet to be completed for a grade.