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### Unit 11: Lesson 2

Perimeter of polygons with missing side lengths

# Find a missing side length when given perimeter

## Problem

The perimeter of the figure is 31, start text, space, m, end text.
What is the length of the missing side?
start text, m, end text
A four-sided figure with sides labeled as follows: 8 meters 6 meters, question mark meters, and 10 meters.
Stuck?
Stuck?