You are designing a rectangular pet pen for your new baby puppy. You have 30 feet of fence barrier (perimeter). On a whim, you decide that you would like the length to be 6\frac{1}{3}6 3
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feet longer than the width. Let x represent the width. Find the value of x.

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?