Which set of ordered pairs represents y as a function of x? {(0, 0), (-1,2), (-1,-2), (-2, 4), (-2,-4)}
{(0, 0), (1, 1), (2, 4), (3,9), (3, 16)}
{(0,0), (0, 1), (0, 2), (0,-1), (0.-2)}
{(0, 0), (-1, -0.5), (-2, -1), (-3,-1.5. (-4,-2)}

Click on the graphic until you find the right quotient. (36xa - 30xb) ÷ (-6x2)

When y’all answer can y’all explain too !

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?