How do you we use p.e.m.d.a.s. to evaluate expressions?

Answer 1

"PEDMAS" is not really a tool to use as much as it is a trick to remember the correct order of operations when evaluating an expression. It is an acronym that indicates the order in which operations should be done, and it stands for:

Parentheses

Exponents

Division

Multiplication

Addition

Subtraction

Another common version of it is "BEDMAS", which means the same thing, but with the word "Brackets" instead of "Parentheses".

For example, if you want to simplify this expression:

(2 + 5) × 3 - 42 / 2 + 1

We would do it in this order:

First parentheses:

7 × 3 - 42 / 2 + 1

Then exponents:

7 × 3 - 16 / 2 + 1

Then division and multiplication (technically, they are the same operation, and can be done in either order):

21 - 8 + 1

Finally, addition and subtraction (again, they are really the same operation, so they too can be in either order):

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