Look at the figure below:

what is the length, in units, of segment cd?

1) 8
2) 9
3) 6.25
4) 7.25

In the first triangle 80+20+p=180 (since sum of all angles of a triangle is 180)so p= 80also in second triangle 55+45+q=180 (since sum of all angles of a triangle is 180)so q=80so we can conclude that p=80 degrees q=80 degrees so p=q=80 degreeshence option b is correct