Chantal is building a fence around her swimming pool. the pool is 25 ft long and12 ft wide, and she wants a 6-ft wide rectangular walkway around the entire pool. how much fencing will she need?

25 /12*6 =12.5 or thats what i got 

“exterior angles of triangles. an exterior (or external) angle is the angle between one side of a triangle and the extension of an adjacent side. try this drag the orange dots on any vertex to reshape the triangle.” look to get to the answer i explained what it means and other things i hope it you .