Lines A and B are parallel. If Angle 4 is 100 degrees, then angle 1 is

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.Lines A and B are parallel. If Angle 4 is 100 degrees, then angle 1 is

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.Detailed Explanation

Two angles that form a straight line add up to 180 degrees. If Angle 4 is 100 degrees then Angle 1 must be 80 degrees.