Linear Function

A linear function is given as f (x) = mx + c where m is the slope of the graph and c is the y-intercept.

Slide the values of m and c to observe the changes of graph f (x) = mx + c. You may realize that for

1. m > 0, the graph is increasing;
2. m = 0, the graph is constant;
3. m < 0, the graph is decreasing;

while for

1. c > 0, the graph has positive y-intercept;
2. c = 0, the graph passes through the origin;
3. c < 0, the graph has negative y-intercept.

Betty, Created with GeoGebra