The sum of the first 4 terms is 671? If the number increased by 20% each time, what is the starting number?

This is about circle theorems. someone asap : (

Scott’s bank account showed a balance of $750 on sunday. during the next five days, he made one deposit of $140 and numerous withdrawals of $180 each. let x represent the number of withdrawals that scott made. write an inequality that can be used to find the maximum number of withdrawals that scott could have made and maintain a balance of at least $100. do not use a dollar sign ($) in your response.

Solve the system of equations using the substitution method. {y=−3x+7x=−2y−16 enter your answers in the boxes.