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Please help!
find measure of CDE ​

Please help! find measure of CDE ​-example-1
User Cec
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1 Answer

5 votes

Answer:

170

Explanation:

A heptagon's internal angles add up to 900 degrees.

So:

(2x-13)+(3x-8)+(2x-3)+(2x-7)+(3x-1)+(2x+11)+(2x+9) = 900

16x - 12 = 900

16x = 912

x = 912/16

x = 57

So:

3x - 1 = 3 * 57 -1 = 170