Final answer:
When solving for a variable, we invert the order of operations (reverse BIDMAS/PEMDAS) to effectively isolate and determine the value of the variable. This often involves carrying out subtraction or division before other operations, contrary to the regular order of operations.
Step-by-step explanation:
When you are solving for a variable in an algebraic equation, you are essentially aiming to isolate that variable on one side of the equation. This often requires you to inverted the order of operations, otherwise known as the reverse of BIDMAS or PEMDAS (brackets, indices or parentheses, division/multiplication, addition/subtraction).
Let us take an example: 3x + 5 = 20. Here, to solve for x, you would subtract 5 from both sides first, which is the reverse of the PEMDAS/BIDMAS order (where addition and subtraction come last). After subtraction, you are then left with 3x = 15, which you can solve for x by dividing 3, again a reversal of the normal order of operations. Thus inverting the order of operations when solving for a variable helps to efficiently isolate and determine the value of the variable.
Learn more about Order of operations