Question

If a and b are parallel lines and m 3=128 what is the measure of 8

Answer 1

The correct question is 
If a and b are parallel lines, and m∠3 = 128°, what is the measure of ∠8?

see the attached drawing

we have
m∠3 = 128°
m∠3 = m∠7---------------- > Corresponding Angles
180°=m∠7+m∠8---------- > Supplementary Angles
therefore
m∠8=180°-128°=52°

the answer is the m∠8 is 52°