To find the perimeter, you have add all the sides up.
So. . .
1) We first know that this is a rectangular computer, meaning the shape is a rectangle.
2) We have to add 50 to 36; 50 + 36 = 86
3) Then do the same thing, because we only added two sides and we have to add two side more; 50 + 36 = 86
4) Add 86 to 86; 86 + 86 = 172
Your answer is 172 centimeters. Any question, just comment it down below! :)
