Finding Missing Side Lengths
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Objective
I can use addition and subtraction to find the unknown side length of a polygon.
Part 1 of 3
Warm-up video
Unknown Channel · 5:00
We don't generate video — this one is by Unknown Channel on YouTube. The practice questions and exit ticket below were drafted by AI for this objective, and every question is editable in the teacher guide.
Part 2 of 3
Practice
7 questions
Explain in your own words how to find a missing side length of a shape when you know the lengths of some of the other sides.
Look at this shape: It has sides of 3 cm, 5 cm, 2 cm, and a missing side. If the top side is 5 cm and part of the bottom side is 2 cm, what operation (addition or subtraction) would you use to find the missing side?
Part 3 of 3
Exit ticket
Quick comprehension check
“A shape has a top side of 6 cm. The bottom side has two parts. One part is 2 cm. What is the length of the other part of the bottom side if the entire bottom side is 6 cm? A shape has a left side of 8 inches. The right side has two parts. One part is 3 inches. What is the length of the other part of the right side if the entire right side is 8 inches? A shape has a side that is 10 meters long. This side is made up of two smaller parts. If one part is 4 meters long, how long is the other part?”
Sample answer included in the free materials
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