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The diagram shows an equilateral triangle touching two straight lines.
What is the sum of the four marked angles?
If you liked this problem, here is an NRICH task which challenges you to use similar mathematical ideas.
Triangle in a Corner
Age 11 to 14
ShortChallenge Level 
The diagram shows an equilateral triangle touching two straight lines.What is the sum of the four marked angles?
If you liked this problem, here is an NRICH task which challenges you to use similar mathematical ideas.
This problem is taken from the UKMT Mathematical Challenges.
You can find more short problems, arranged by curriculum topic, in our short problems collection.
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