Identify the y-intercept. Then, find another point that lies on the grid.
Slope: - 1/4 y-intercept: (0,3)
Practice makes perfect
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. Let's start with the y-intercept.
Finding the y-intercept
Observe the given graph.
We can see that the function intercepts the y-axis at (0, 3). This means that the value of b is 3.
Finding the 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 will be able to identify the slope m using the rise and run of the graph.
Here have identified (4,2) as our other point. Traveling to this point from the y-intercept requires that we move 1 step vertically in the negative direction and 4 steps horizontally in the positive direction.
rise/run=- 1/4 ⇔ m= - 1/4
