Answer:
a. 138
b. 180
c. 222
d. 138
Step-by-step explanation:
Since QS and RT are straight lines, they each have an angle measure of 180 degrees. Using this info, you can subtract 48 from 180 to find RS. Another thing to note is that when 2 lines intersect, the opposite angles are always equivalent, so in this case, QR and ST are both 42 degrees and RS and QT are both 138 degrees.
To solve these arc measures, all you need to do is add up the angles that you need to find.
