SOLUTION: one decreased by the difference between 18 and seven times a number is -9

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Question 1035853: one decreased by the difference between 18 and seven times a number is -9
Answer by Cromlix(4381) About Me  (Show Source):
You can put this solution on YOUR website!
Hi there,
one decreased by the difference
between 18 and seven times a number is -9.
Make the number = x
1 - (18 + 7x) = -9
Multiply out.
1 - 18 - 7x = -9
Collect like terms:
-7x = -9 + 18 - 1
-7x = 8
x = 8/-7
The number = -8/7
Proof:
1 - (18 + 7x) = -9
1 - (18 + 7(-8/7)) = -9
1 - (18 - 8) = -9
1 - (10) = -9
1 - 10 = -9
-9 = -9.
Hope this helps :-)