A cow is tethered by a 50-meter rope to a rectangular barn. The dimensions of the barn are 60 m x 30 m. The rope is fastened to a hook that is 10 meters from the corner on the longest side of the barn. Over exactly how much ground can the cow graze? (Assume that the cow cannot pass through the barn. He must graze outside only.)
I have drawn this problem as follows (not drawn to scale):
I am not even sure if the picture is correct, or how to apply any formula knowledge into this problem. In your explanation, please explain how and why you wrote the steps to your solution.