Thread: What is the order of operation in this equation

3² - 4 x 2 x (-1)

I know the answer is 17 but I dont know how to work this out without a calculator

Please help

Do you know BODMAS? Brackets, (Powers) Of, Division, Multiplication, Addition, Subtraction?

First evaluate anything in brackets (there aren't any), then any powers, then any multiplications and divisions (from left to right), and finally any additions and subtractions (from left to right).

I prefer "Please Excuse My Dear Aunt Sally" or "PEMDAS": first do what is inside parentheses (or brackets or any "grouping" symbols), then exponents such as , then multiplications and divisions (the order of those is not important) finally additions and subtractions. For your problem, calculate and the product (4)(2)(-1)= -8 and finally do the subtraction: 9- (-8)= 9+ 8.

Originally Posted by HallsofIvy

I prefer "Please Excuse My Dear Aunt Sally" or "PEMDAS": first do what is inside parentheses (or brackets or any "grouping" symbols), then exponents such as , then multiplications and divisions (the order of those is not important) finally additions and subtractions. For your problem, calculate and the product (4)(2)(-1)= -8 and finally do the subtraction: 9- (-8)= 9+ 8.

The order of the multiplications and divisions, and the additions and subtractions IS important. Even though multiplication and division have equal power, you still need to work LEFT TO RIGHT. Same with the additions and subtractions.