SOLUTION: Twice the difference of a number and 7 equals 9

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Question 997175: Twice the difference of a number and 7 equals 9
Answer by Theo(13342) About Me  (Show Source):
You can put this solution on YOUR website!
x represents the number.

2 * (x - 7) = 9

divide both sides by 2 to get x - 7 = 4.5

add 7 to both sides to get x = 11.5

to confirm, test our the original assmption.

twice the difference of a number and 7 equals 9.

the number is 11.5
11.5 - 7 = 4.5
two times 4.5 = 9.

looks good.