To start, the top right angle and the bottom left angle are alternate interior angles, making them congruent. The same justification goes for the angles in the top left and bottom right. With this in mind, 37° + 44° = 81°. Every triangle's angles always add up to 180°, meaning that 180° - 81° = 99°. Because angle n and the angle we just found to be 99° are supplementary, they also add up to 180°, therefore 180° - 99° = 81° which is the value of angle n.
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