# Angles 1

Is it true that adjacent angles have common arm?

**Result**### You need to know the following knowledge to solve this word math problem:

## Related math problems and questions:

- 4-gon

Is it true that a 4-gon whose two sides are parallel and the other two have equal length is a parallelogram? - Line

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A trapezium where AB is parallel to CD, has angle A : angle D = 4 :5, angle B = 3x-15 and angle C = 4x+20. Find angle A, B, C and D. - Height

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