Question

45°
X 100°
y = [ ? jº

Answer 1

y = 55°

Explanation:

The exterior 100° angle is equal to the sum of the remote interior angles:

100° = 45° +y

y = 100° -45° = 55°

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Additional comment

The angle marked x is the supplement of 100°:

x = 180° -100° = 80°