If ∠2 = 50° and lines a and b are parallel, which of the following angles cannot be determined? *-∠1-∠3-∠4-∠8-None of the above
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If you have the angle 2, you can deduce its the supplement,which is the angle 4. In this case the supplement is equal to 130°.
Angle 2 and angle 6 are corresponding angles, so they have the same measure.
Angle 4 and angle 8 are corresponding, so they have the same measure.
Angle 2 and angle 1 are vertically opposite angles, so they have the same measure.
Angle 5 and angle 6 are vertically opposite angles, so they have the same measure.
Angle 7 and angle 8 are vertically opposite angles, so they have the same measure.
Angle 4 and angle 3 are vertically opposite angles, so they have the same measure.
Therefore the answer is None of the above.