Y= -3x^3+17x^2-10x If you graph this there should be 3 points but when I solve it, I only get 2 points being 5 and 2/3 which is .6 in decimal form. Am I doing this right? What’s the process

Money off coupons have been circulated to 300 households. only 2/5 of these were redeemed (used) in the local supermarket to get a free shampoo. what fraction of coupons were unused? (ps: write how you got the answer)