Answer:
x = 6
Step-by-step explanation:
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
Answer:
x = 50 + 10(CD)
Step-by-step explanation:
CD = 4
x = 50 + 10(4)
x = 50 + 40
x = 90
x = amount spent.
y = 5x, so 5 is the constant of proportionality
