2x = 18
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x = 18 : 2 =
x = 9
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(2*9 : 3) + 1 = 7
6 + 1 = 7
You cross the date line into Monday.
_____
The next day after Monday is Tuesday. (I find it difficult to tell the intent of the question.)
Answer: The cost will be the same on month 5.
Step-by-step explanation:
x = number of months
50 + 100(x) = $550
200 + 70(x) = $550
x = 5
The answer is A, B(4, 4) and D(4, -3).
Hope I helped!!!! :D