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Help please urgent please​

Help please urgent please​-example-1

1 Answer

9 votes

Answer:

30°

Explanation:

From what I can picture, I suppose that ∠CDE is an exterior angle and is supplementary to ∠CDB.

Since ∠CDE is supplementary to ∠CDB, m∠CDB measures:


180-(7x-19)=199-7x

And since the sum of interior angles of a triangle is 180°, we can write:


(2x-1)+(199-7x)+(x+10)=180\\-4x+208=180\\-4x=-28\\x=7

Substitute x back to ∠CDE:


(7x-19)=(7(7)-19)\\=49-19\\=30

User TBrenner
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