Find g(x), where g(x) is the reflection across the y-axis of f(x)=|x|. Write your answer in the form a|x–h|+k, where a, h, and k are integers.

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?