A certain number, increased by 18, is three times the original number,diminished by 8. Find the number

It can be easly solved by using equivalent solving or however you call it in english language in my language (slovenian) it is ekvivalentne enačbe. Well, let's say a number is x. Then the equation looks like that:

x + 18 = 3x - 8

First, you need to put the parts with x on the left side, and the parts of equation without x on the right side. Important is, that when you move the part of equation from one side to another, it changes from - to +, or from + to -. Than, the equation looks like that:

x - 3x = -8 -18

Now calculate the left and the right part of the equation. If there is no number before x, than it means the number should be 1.

1x - 3x = -26

- 2x = -26

Now search for the x;

-2 x = -26

    x = -26 : (-2)

    x = 13

Let n be the number ... so....

n + 18  = 3n - 8      add 8 to both sides......subtract n from both sides

26  = 2n                  divide both sides by 2

13 = n