Question

the sum of twice a number and 15 less than the number is the same as the difference between -19 and the number. What is the number?

Answer 1

-1

Explanation:

Twice a number: 2n.

15 less than the number: n-15.

The sum of those: (2n) +(n-15) = 3n-15.

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The difference between -19 and the number: -19-n

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These values are the same, so we have ...

3n -15 = -19 -n

4n = -4 . . . . . . . . add n+15 to both sides

n = -1 . . . . . . . . . divide by -4

The number is -1.