Instead of subtracting 6 from 12 then dividing they added 6 to 12 & ended up with 18. 18 by 2 is 9.
If this is in value, you would have $5,060. If you mean bills it would be 560.
A1 = first term
a1 = 15
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d = common difference
d = (second term) - (first term)
d = a2 - a1
d = 9-12
d = -3
The negative common difference indicates that the terms are decreasing
Each time we subtract 3, or add -3, to get the next term.
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nth term of arithmetic sequence
an = a1 + d(n-1)
an = 15 + (-3)(n-1)
an = 15- 3n + 3
an = 18 - 3n
Answer is choice D
X <0 means x would be negative.
For x/y, a negative divided by a positive would give a negative answer.
A negative multiplied by a positive would result in a negative.
The answer would be B. Negative
