D) f(n) = 3 + 4(n-1)
3 = 1st term
4 = common difference among the terms
n = term number you are looking for.
To check: 3, 7, 11, 15, ...
f(1) = 3 + 4(1-1) = 3 + 4(0) = 3 + 0 = 3
f(2) = 3 + 4(2-1) = 3 + 4(1) = 3 + 4 = 7
f(3) = 3 + 4(3-1) = 3 + 4(2) = 3 + 8 = 11
f(4) = 3 + 4(4-1) = 3 + 4(3) = 3 + 12 = 15
0.25 = 25/100
to simplify 25/100, divide 25 from both the numerator and denominator.
25/25 = 1
100/25 = 4
1/4 is the simplest form
C. 1/4 is your answer
hope this helps
All you need to do is put 45 over 100 to make it 45/100, then simplify down until you get your answer. The answer is 9/20 though. There may be better ways, but that's how I do it.
The answer to the variable r is r=-4