4. A line passes through the points and . Write its equation in slope-
   intercept form.

To find the equation of the line passing through the points and , we first note that both points have the same y-coordinate, which means the slope of the line is . Thus, the line is horizontal. The equation of a horizontal line is of the form , where is the y-coordinate of the points. Therefore, the equation in slope-intercept form is .

Now, how fun is it to visualize that this line runs parallel to the x-axis, never changing its height? As you travel infinitely to the left or right, you stay at the same elevation, like a leisurely stroll on a perfectly flat path.