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The reflex angle dob measures 3.5y and aod measures y. Find the measure of the non-reflex angle dob in degrees.

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Final Answer:

When a triangle has a reflex angle, the other two angles are called non-reflex. In this case, the non-reflex angle dob measures 146.5 degrees when the reflex angle dob is known to be 360 degrees minus the sum of both angles.

Explaination:

In a triangle, the sum of the angles is 180 degrees. When one angle is a reflex angle (greater than 180 degrees), the other two angles are called non-reflex angles. In this case, we have two non-reflex angles, dob and aod, and a reflex angle, dob.

Let's call the reflex angle dob and the non-reflex angle dob in degrees d. The other non-reflex angle aod is also in degrees y.

The sum of the angles is:

d + d + y = 180 degrees

Substituting d = 360 - (d + y):

360 - (d + y) + d + y = 180 degrees

Simplifying:

2d = 180 degrees

d = 90 degrees (non-reflex angle dob)

Substituting d = 90 degrees in the first equation:

90 + y + (360 - (90 + y)) = 180 degrees

Simplifying:

y = 60 degrees (aod)

The measure of the non-reflex angle dob in degrees is:

dob = 360 - (90 + 60) = 146.5 degrees.

User Timothy Swan
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