(picture) Does shape C have 4 right angles? (ignore A and B)

Which undefined geometric term is described as a location on a coordinate plane that is designed by an ordered pair (x,y) ?

The amount spent on food and drink by 20 customers is shown below what is the modal amount spent ?

Asquare and an equilateral triangle have the same perimeter. each side the triangle is 4 inches longer than each side of the square. what is the perimeter of the square