Substitute 0 for one variable and solve. Repeat for the other variable, then graph the points.
Practice makes perfect
We will graph this equation by finding and plotting its intercepts. Then, we will connect them with a line. To find the x- and y-intercepts, we will need to substitute 0 for one variable and solve. After that, repeat for the other variable.
Finding the x-intercept
Think of the point where the graph of an equation crosses the x-axis. The y-value of that ( x, y) coordinate pair is equal to 0, and the x-value is the x-intercept. To find the x-intercept of the given equation, we should substitute 0 for y and solve for x.
An x-intercept of -9 means that the graph passes through the x-axis at the point ( -9,0).
Finding the y-intercept
Let's use the same concept to find the y-intercept. Consider the point where the graph of the equation crosses the y-axis. The x-value of the ( x, y) coordinate pair at the y-intercept is 0. Therefore, substituting 0 for x will give us the y-intercept.
