The product of x and 7 is at least 21

Nine more than four times a number is the same as one less than twice the number. find the number?

Ray ce is the angle bisector of zacd, which statement about the figure must be true? mzecd-mzecb mzace « 4mzacd zace - zdcb zecd zacd save and exit

Which one ? is the answer and how to find this answer