Find the given?

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1 Answer
Feb 23, 2018

A) 30 degrees

Explanation:

The first step is to find angleC.

We know that angleA = 30 and angleB = 90. Since all triangles have angles that add up to 180,

angleC = 180 - 30 - 90
angleC = 60

We can use this to complete the next step: finding angleCEB (this is complementary with angleCED, so we'll be able to find angleCED by subtracting angleCEB from 90).

We can do this by taking triangleCEB as its own triangle. angleB is still 90. angleECB is angleC-:2, since bar(CE) bisects angleC. So angleECB = 30.

angleCEB = 180 - 90- 30
angleCEB = 60

angleCED = 90 - 60
color(red)(angleCED = 30)