Round 790 to the nearest hundred? Hurry pls and please don't answer if you know you wrong

3x + 4y = 5 x- 3y = -7 solve by substitution

Find the value of x to the nearest tenth.

Problem 3 a bank charges a service fee of $7.50 per month for a checking account. a bank account has $85.00. if no money is deposited or withdrawn except the service charge, how many months until the account balance is negative