How do you evaluate #22 -: 2 + 9 - 4^2+18#?

1 Answer
Mar 13, 2017

#22#

Explanation:

Use the order of operations (precedence) rules: Parentheses, Exponents, Multiplication, Division, Addition, Subtraction from left to right. An acronym PEMDAS to help you remember is "Please Excuse My Dear Aunt Sally".

Although this is a simple way to remember, multiplication and division are on equal footing, as well as addition and subtraction. This means the Left to Right order is important.

#22 -: 2 + 9 - 4^2 + 18#

First step: #4^2 = 16#

Second step: #22 -: 2 = 11#

Third step: #11 + 9 = 20#

Fourth step: #20 - 16 = 4#

Fifth step: #4 + 18 = 22#