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Three times the difference of a number and two is equal to the sum of the number and twelve.

User Stwe
by
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1 Answer

3 votes

Answer:

x=-21

Explanation:

The difference of a number and 3 is x - 3

The sum of the number and 5 is x + 5

Twice the difference of a number and 3 is therefore 2(x - 3)

Three times the sum of the number and 5 is therefore 3(x + 5)

These last two terms are equal. In equation form this is:

2(x - 3) = 3(x + 5)

2x - 6 = 3x + 15

Get rid of the 3x on the right side by subtracting 3x from both sides and you have:

-x - 6 = 15

Get rid of the -6 on the left side by adding 6 to both sides to get:

-x = 21

You are trying to solve for +x. To change the left side of this equation to +x multiply

both sides by -1 and you change the equation to:

x = -21

Hope this helps you to understand the problem.

User Custodio
by
3.8k points