Explanation:
Slope-intercept form: y=mx+b
The slope is 8. This means that 8 multiplied by x is the slope of the line, and if there was no y-intercept then the first point would be (1,8) so 8 would be unit rate.
The y-intercept is -12. This means that though the slope of the line would still be 8, you move the point down on the y-axis by 12. The y-coordinate will always be 12 less than 8 times x