5x+7y=-11 and 5x-3y=19 solve by elimination

How many square centimeters of wrapping paper will be used to wrap the shoe box?

You went to a restaurant and spent $53.25 on the meal. there was a 6% sales tax. what was the amount of money, not including a tip, you spent at the restaurant?

Geometry - finding area of regular polygons and sectors (check my math, i can’t find the error)