What is the measure of angle E?

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What is the measure of angle E?

by swerve » Sat Dec 30, 2017 7:06 am
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In the diagram above, angles measures in degrees are marked as shown, and segment BC is parallel to line AD. What is the measure of angle E?

(A) 30°
(B) 35°
(C) 40°
(D) 45°
(E) 50°

The OA is D.

Please, can any expert explain this PS question for me? I tried to solve it but I don't understand it. I need your help. Thanks.

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by EconomistGMATTutor » Sat Dec 30, 2017 1:20 pm
In the diagram above, angles measures in degrees are marked as shown, and segment BC is parallel to line AD. What is the measure of angle E?

(A) 30°
(B) 35°
(C) 40°
(D) 45°
(E) 50°

The OA is D.

Please, can any expert explain this PS question for me? I tried to solve it but I don't understand it. I need your help. Thanks.
Hi swerve,
Let's take a look at your question.

In triangle ABC,
$$\angle BCA=180-\angle BAC-\angle ABC$$
$$\angle BCA=180-75-65$$
$$\angle BCA=40$$

Since, segment BC is parallel to the line AD, therefore, alternate interior angles are congruent.
$$\angle CAD=\angle BCA$$
$$\angle CAD=40$$

Consider triangle ADE,
$$\angle E=180-\angle D-\angle DAE$$
$$\angle E=180-95-40$$
$$\angle E=45$$

Therefore, Option D is correct.

Hope it helps.
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