How do you write twice the difference of a number and 9 equals 2 as an equation?

Hint: If you need to answer these types of questions, then you need to be clear with the language. Unless and until you understand the question clearly, you cannot answer. Take the number as $ x $ and write the equation with the help of the hint, which is given in the question.

Complete step-by-step answer:
If you find these types of questions, you must know to pick up the numbers which are given in the question. The numbers which are given in the question are 2(twice), $ x $ (number), 9 and 2. Now you have to use the hint to arrange all these numbers in an equation. To make you understand clearly, I would like to divide the sentence into three small words or sentences. The small words or sentences are “twice the”, “difference of a number ( $ x $ ) and $ 9 $ ”, and “equals $ 2 $ ”. Now consider “twice the”, whenever you find the word “twice” in a sentence you have to know to write $ 2 $ . If you find the twice with “the”, then you have to write “ $ 2() $ ”. And that’s it we have completed the first par.
Then consider the word “the difference of a number and $ 9 $ ”, now fill this inside the open bracket present in “ $ 2() $ ”. The second one tells us to subtract the number ( $ x $ ) and 9, which is $ x - 9 $ . Now fill this inside the open bracket. And hence it becomes,
 $ 2(x - 9) $
Now consider the final small sentence “equals $ 2 $ ”, which we can easily put as “ $ = 2 $ ”, And therefore the required equation is,
 $ 2(x - 9) = 2 $
So, the correct answer is “ $ 2(x - 9) = 2 $ ”.

Note: The above-mentioned method can be remembered as a formula for solving this type of question. Be strong with the language while attending these types of questions, because there are many questions which may confuse you the most. This is easy to choose when you are writing an exam, it takes less time to solve, only when you are thorough with this concept.