Wave erosion can cause a coastline to recede at a rate of a few centimeters each year. Suppose a beach recedes 2 centimeters each year. In four years, how many centimeters will the beach recede?
You have Years thats your Y and over the course of 2cm each year. 2y. x is the total beach erosion. over four years the beach will reside: x = 2(4) so a total of 8 CM.