Alex N. answered • 08/27/14
Tutor
New to Wyzant
Computational Biologist / PhD Candidate Looking to Nerd Out!
Hi Katrina,
The perimeter of a surface is the sum of its edge lengths. If you have a square with 5-inch-long sides, for example, then the perimeter of the square is equal to 5 in. + 5 in. + 5 in. + 5 in., which adds up to 20 inches.
Similarly, if you have a triangle with side lengths of 3 inches, 4 inches, and 5 inches, then the perimeter of that triangle would be 3 in. + 4 in. + 5 in., which equals 12 inches.
The most important trick for calculating the perimeter of a surface is figuring out what all of the shape's side lengths are equal to -- once you know this, calculating the perimeter is just a matter of adding up the shape's side lengths.
The answer to your question about the perimeter of the 144 square foot room will depend on the lengths of the room's sides (or walls). These lengths will depend on the shape of the room, since rooms with different shapes can have different perimeters but still be 144 square feet. For example, the perimeter of a square room with 12-foot-long sides will be smaller than the perimeter of a rectangular room with two 24-foot-long sides and two 6-foot-long sides (for practice, you could calculate these perimeters and check that the rectangular room has a larger perimeter than the square room).
I'm guessing there's some more information hidden in the phrasing of the problem to help you determine what the side lengths of the room are (specifically, the shape of the room). Remember, once you know the side lengths you just need to add them together to get the perimeter!
I hope you find this helpful!
