Seeing Expression As A Block

In maths, the many expressions and numbers confuse the working mind when you are not alert.

This is so especially when you do subtraction.

Do you look at expression as a block or isolated terms?

Let's take an example.

If Z = 2x + 1, and A = x - 1, perform Z - A.

How do you go about this?

Do you directly work the subtraction out, like this :
2x + 1 - x - 1, or

Do you treat the A as a piece or block, like:
2x + 1 - (x - 1)

Looking at expression or numbers, requires "seeing" skill. You need to see with your mathematical mind.

Always understand that expressions and numbers alike are to be operated as a whole.
The use of parentheses is a good habit.

Parentheses can be used to group the expression or target, and make it visually clear to the mind that you are working on a piece of information.

From the above 2 ways of seeing the Z - A, you will notice that the first work-out will give a mistake that is very popular among math learners. It is always repeated even after tons of corrections.

The true mistake lies in the way you look at numbers or maths expressions.

If you can't and always make careless mistake, apply the parentheses ( or bracket) to the desired target.

Know your strength and weakness while doing maths. It will at least help reduce some careless mistakes along the way.

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U
Smile... Maths is interesting!

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