Exercise 8 Page 368

Equations written in slope-intercept form follow a specific format. y= mx+ b In this form, m is the slope and b is the y-intercept. We need to identify these values using the graph.

y-intercept

The y-intercept is the y-value where the line crosses the y-axis.

We can see that the function intercepts the y-axis at (0, 3). This means that the value of b is 3. y= mx+ 3

Slope

To find the slope, we will trace along the line on the given graph until we find a lattice point, which is a point that lies perfectly on the grid lines. Doing so, we can identify the slope m using the rise and run of the graph.

Here we have identified the (3,2) as our other point. Traveling to this point from the y-intercept requires that we move 3 steps horizontally in the positive direction and 1 steps vertically in the negative direction. rise/run=- 1/3 ⇔ m= - 1/3

Writing the Equation

Now that we have the slope and the y-intercept, we can write our final equation. y= - 1/3x+ 3 This corresponds to option F.