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43 votes
DE is tangent to Circle C at point D.

What is the measure of Enter your answer in the box.

DE is tangent to Circle C at point D. What is the measure of Enter your answer in-example-1
User Davidcrossey
by
3.1k points

1 Answer

13 votes
13 votes

Answer:

39°

Explanation:

A radius of a circle (segment CD) drawn to the point of tangency (D) intersects the tangent (line DE) at a 90-deg angle.

That makes m<D = 90.

m<D + m<C + m<E = 180

90 + 51 + m<E = 180

m<E = 39

User Krackmoe
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2.5k points