Below are examples of working that are not acceptable.
Illustration 1: "Choo-choo train" working
All steps are presented in a single line, continuously.
This is going to be confusing when handling equations.
General guide: No more than one equal sign (=) in each line of working.
Illustration 2: Fragmented working
An arithmetic expression is broken down into parts; and you work on individual parts before putting them together.
As we are handling numbers involving negative numbers, there will be a high tendency to make mistake in the sign when 'putting' the parts together.
General guide: Identify the portion that you intend to work on, copy the remaining components in the arithmetic expression.
1. Work on the terms within the bracket(s) first
2. While evaluating the square/ cube terms, the remaining terms are copied to the new line
3. "Remove" all brackets before working from left to right.