Answer:
See below.
Step-by-step explanation:
1/2 = shrink by a factor of 1/2.
+7 = moved up 7 units.
First, we inspect what type of sequence is the order of the coordinates:
a2 = 1
a3 = 2
a4 = 4
Getting the difference,
a3 - a2 = 1
a4 - a3 = 2
The differences are not equal; hence, the sequence is not arithmetic.
Getting the ratio:
a3/a2 = 2
a4/a3 = 2
The common ratio is 2. Using the general form for a geometric series:
an = a1 r^(n-1)
If n = 2
1 = a1 (2)^(2-1)
a1 = 1/2
So,
an = (1/2) (2)^(n-1)
The answer is the first option.
My calculator says bad expression.
2/3 and 12/18 are equivalent fractions, and 12+18 = 30 so the answer is 12:18