To solve for simple perimeter, students add up all the side lengths of the given shape. 

When students are given the perimeter and a few of the side length, students are required to solve this as a         2-step problem. 

• • • • 1. Add all the known side lengths

        2. Subtract the known side lengths from the perimeter

Students solve for perimeter with irregular, the same way they do with regular shapes. 

• • • • If you are finding perimeter, add up all the side lengths

      • If you are finding the missing side, add up all the known side lengths and subtract that total from the given perimeter.  

Multiple missing sides can be figured out by using a number bond strategy. All vertical lines go together and all horizontal lines go together. 

• • • • In the examples to the left the blue number bond shows the connection between the horizontal lines on the irregular shape. 

      • The red number bond shows the connection between the vertical lines on the irregular shape.