The equation of a straight-line graph can contain; an x term, a y term, and a number. Although some equations for straight lines might have only two of those, like an x term and a number, eg x=5. read more
You can see the effect of different values of m (the slope) and b (the y intercept) at Explore the Straight Line Graph Other Forms We have been looking at the "slope-intercept" form. read more