Warm Up:

Slope Intercept Form from a Table

Slope as a Pattern

Y-Intercept Graphically On a graph, the Y-intercept is where the graph crosses the Y-Axis. We represent this with the point (0,b). Table In a table, the Y-Intercept happens when X=0. This comes from the fact that the Y-Intercept on a graph is represented by the point (0,b). The line crosses the Y-Axis at the point (0,4). The Y- Intercept is 4. The Y-Intercept for the Table is 0 because when X=0, Y=0.

Example 1 Find the equation in Slope Intercept Form for the following Table:

What happens if X=0 does not appear in the Table? If X being 0 in the table does not appear, we have to work backwards in both X and Y until X=0. When we work backwards, we do the opposite pattern in both X and Y. If we add something in Y, we subtract that number when working backwards. If we subtract something in X, we add that number when working backwards.

Example 2 Find the equation in Slope Intercept Form for the Following Table: To find b, we work backwards by doing the opposite pattern in X and Y Our pattern in Y was to subtract 3. The opposite of subtracting 3 would be to add 3 Our pattern in X was to add 1. The opposite of adding 1 would be to subtract 1. We extend our table to the left until we reach X=0. b= Y when X is 0=