Question 311557
find three consecutive integers such that three times the first minus the second is one more than third 
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1st: x
2nd: x+1
3rd: x+2
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Equation:
3(x) - (x+1)= x+3
3x-x-1 = x+3
2x -1 = x+3
x = 4
x+1 = 5
x+2 = 6

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2. A number is two times the difference between eighteen and a number find the number
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Let the number be "x":
x = 2(18-x)
x = 36 -2x
3x = 36
x = 12
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Cheers,
Stan H.