12 plus 6 times a number is 9 times the number The phrase a number means an arbitrary variable. Let's call it x. 6 times a number is written as: 6x 12 plus 6 times the number means we add 6x to 12: 12 + 6x 9 times a number is written as: 9x The phrase is means an equation, so we set 12 + 6x equal to 9x 12 + 6x = 9x <-- This is our algebraic expression If the problem asks you to solve for x, then you type this expression into our search engine and you get: x = 4