Given: Circle O has a diameter AB with points A(5, 19) and B(17,3).
Circle O has a chord CD with points C(11,1) and D(20.6,8.2).
Use the theorem that states, "If a diameter of a circle is perpendicular to a chord, then the diameter
bisects the chord."
Which is a key statement in the proof that diameter AB bisects chord CD?

Isuck at math ; ^; m a student solved this problem and said the answer is 3 feet. chase had a roll of ribbon that contained 7 7/8  feet of ribbon. he cut off one piece that was 3 5/8  feet long and another piece that was 1 1/4  feet from the roll. how much ribbon was left on the roll? is the student's answer reasonable? yes, the answer is reasonable. no, the answer is not reasonable. it should be about 2 feet. no, the answer is not reasonable. it should be about 13 feet. no, the answer is not reasonable. it should be about 4 feet.

Varies inversely with x. if y=8.5 when x=-1 find x when y=-1

Either enter an exact answer in terms of \piπ or use 3.143.14 for \piπ and enter your answer as a decimal.