Respuesta :
30 degrees, the two line must have the exact same sloop, or in this case the same degree.
Answer:
It must be decreased by 30 degrees
Step-by-step explanation:
Two parallel lines are those which have equal slopes (m). So, if ac is parallel to bd and the slope of one of them is decreased by 30 degrees, then the slope of the other line must also be decreased by 30 degrees.
