Since two people take both courses, we can subtract two from 7, 8, and 21, giving us 5, 6, and 19.
Add 5 and 6 together to get 11. Since eleven students are in those two groups, we can answer this. The answer will be 11/19.
The answer would be <QRZ
Since you are looking for an angle congruent to <UQR using the alternate interior angles theorem, interior suggests that the angle must be inside the parallel lines, se we can get rid of options <WRT and <TRZ since they are exterior angles
Furthermore, in the alternate interior angles theorem, the two angles must be alternate or opposite of each other which would show that the only possible answer would be <QRZ
hope this helped!
The answer is in the red part but the work is everything on top.
-6 so option D is the answer
