What is the sum of the first 8 terms where an=-n+18?

Iam stuck on one problem. my mind is in absoloute vacation mode. i literallty just need to finish this to be done will give brainliest and all my points if i have to! 1- point free throw and 2- point feild goal. he made 35 shots, and scored 62 points how many of each shot did he make in 1 minute? (i already did the math. he made 8 1-point free throws and 27 2-point feild goals.) 1. write two equations for the problem. (i had a major brain fart.)

Im literally having a mental breakdown

Adam used 1072.4 gallons of water over the course of 7 days. how much water did adam use, on average, each day?