The y-intercept is the y value where the blue line crosses the Y axis which is the vertical black line.
The line crosses at the number 4, so the y-intercept is 4
Answer: D. 4
R = -2 :) hope this helps
21 students because if 6 represents 30% u add 6 two more time which equals 18 and 90% then u add 3 more because it is half of 6. when u add 3 more u will get 21 and 100%