Answer:
B. 9
Step-by-step explanation:
We assume that ...
SU = ST +TU
133 = (9x-5) +(5x+12)
126 = 14x . . . . . subtract 7, collect terms
9 = x . . . . . . . . . divide by 14
F(n-1) = f(n) - 5, based off of the first one
D. (8, -22) is the correct answer
Recall to always convert the mixed fractions to "improper" fractions first,