GeoGebra Classroom

# Discovering the Equation of a Line

## Directions: Begin by turning off Show equation and show slope/intersect

1) using the sliding bars set m to 1 an c to 0, and answer question 1. 2) Now adjust only m and answer question 2. 3) Turn off Show equation 4) Set m to 0 5) Adjust c and answer question 3 and 4. 6) Turn on Show slope/intersect. Adjust both m and c and answer question 5. 7) Answer question 7.

## Question 1

When x=1 what does y equal? When x=2 what does y equal?

## Question 2

What happened to the line and equation as you changed the value of m?

## Question 3

What happened to the line as you changed the value for c?

## Question 4

Do you think c should be added/ subtracted to x or do you think c should multiply/ divide x? Give the reasoning for your answer.

## Question 5

The triangle connected to the line is a visual representation of m and the point is c. With these visual aides turned on what new observations can you make?

## Question 6

Now that you see the equation of the line is there anything that surprised you or was it as you expected? Why were you surprised or what lead you to come the the same equation for a line?