A team is ordering sweatshirts and sweatpants for its players. Each sweatshirt costs $34 and each pair of sweatpants costs $15. Write an algebraic expression to represent the total cost if want sweatshirts and y players want sweatpants.

You are standing next to a really big circular lake. you want to measure the diameter of the lake, but you don't want to have to swim across with a measuring tape! you decide to walk around the perimeter of the lake and measure its circumference, and find that it's 400\pi\text{ m}400? m. what is the diameter dd of the lake?