Triangle Inequality: Open Middle Problem (V1)

Creation of this resource was inspired by this Open Middle problem from Christina Ploeckelman.
Source: Open Middle By: Christina Ploeckelman
Use this app to explore your options here! Suggestion: Keep the solid segment horizontal. Note: Once you form a triangle from any three segments, it will appear!
How many triangles did you find? List all the sets of side lengths you find below.
Is there a relationship among the 3 values that needs to be true in order for these 3 sides to form a triangle? If so, how would you describe it?
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• Unordered list
1. Ordered list
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[code]Code [ctrl+shift+4]
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What causes 3 side lengths to not form a triangle? How would you describe it from what you've seen?
Font sizeFont size
Very smallSmallNormalBigVery big
Bold [ctrl+b]
Italic [ctrl+i]
Underline [ctrl+u]
Strike
Superscript
Subscript
Font color
Auto
Justify
Align left
Align right
Align center
• Unordered list
1. Ordered list
Link [ctrl+shift+2]
Quote [ctrl+shift+3]
[code]Code [ctrl+shift+4]
Insert table
Remove Format
Insert image [ctrl+shift+1]
Insert icons of GeoGebra tools
[bbcode]
Text tools
Insert Math
Math Teachers: For a version of this activity where you can have students choose different fixed perimeters to start, click here.
Close
– Tim Brzezinski

Information: Triangle Inequality: Open Middle Problem (V1)