Answer:
A) X + Y = 12
B) 10Y + x = 10x + Y -18
B) 9Y = 9x -18 multiplying A) by -9
A) -9Y = 9x - 72 adding A and B we get
0 = 18x -90
x = 5
The number is 75
Double-Check
7 + 5 = 12
75 -57 = 18
Explanation:
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