Nope. because 10/15 can be reduced to 2/3 and 12/17 is in its final form.
The prime number is 17 if you look at a multiplication chart there is nothing that equals 17 on there right ?? Even if you divide you will have to find something close to 17 like 16
Answer: X = -1 and Y = 3
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X + Y = 2
X = 2 - Y
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Y = x + 4
Y = 2 - Y + 4
2Y = 2 + 4
2Y = 6
Y = 3
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X + Y = 2
X + 3 = 2
X = -1