In a parallelogram, opposite angles are equal, and adjacent angles are supplementary (they add up to 180 degrees).
Given that the angle at point A measures 155 degrees, the opposite angle at point C will also measure 155 degrees.
Since angles A and B are adjacent, we can find the measure of angle B using the following relationship:
\[ \text{Angle A} + \text{Angle B} = 180^\circ \]
Substituting the value of angle A:
\[ 155^\circ + \text{Angle B} = 180^\circ \]
Now, solving for angle B:
\[ \text{Angle B} = 180^\circ - 155^\circ = 25^\circ \]
Thus, we find that angle B measures 25 degrees, and therefore, angle D (which is opposite angle B) also measures 25 degrees.
To summarize:
- Angle A = 155 degrees
- Angle B = 25 degrees
- Angle C = 155 degrees (opposite angle A)
- Angle D = 25 degrees (opposite angle B)
Therefore, the interior angle measure of point C is 155 degrees.
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