text: When I look at problems like these, I use the two-point formula. Since y is decreasing by a constant amount each time, it's ok to use the two-point formula. Basically, you choose two points...I'll choose (0,1) and (1,-8). Then, you calculate the slope, which is (y2-y1) / (x2-x1). It doesn't really matter which y or x comes first as long as they are correspondent with each other. So, the slope would be (-8-1) / (1-0), which is -9/1, which is -9. Then, plug it back into the equation y = mx + b. So, I'll use the point (0,1). 1 = -9(0) + b. 1 = 0 + b. b = 1. As a result, the function is...y = -9x + 1