Answer: It's b
Step-by-step explanation:
Answer:

Step-by-step explanation:
0 = 0 ± b

* Parallel Lines have SIMILAR <em>RATE OF CHANGES</em> [<em>SLOPES</em>], so −4 remains the way it is.
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Y = total cost
40 = The one time fee
90 = the service charge per month
x = number of months