Try this helpful device when simplifying an expression or equation: "P" for "E" for Parentheses Exponents "M" for Multiply "D" for "A" for "S" for Divide Add Subtract VERY IMPORTANT: Always work your problems from left to right. Parentheses and exponents are of equal importance, and whichever comes first, going from left to right, must be addressed before all other operations. Multiplication and division are the next two operations in line, and are of equal importance. At this point, perform whichever of these operations comes first going from left to right. Finally, you may add or subtract, depending upon which of these operations appears first, going from left to right. Note: Parentheses are grouping symbols. Other grouping symbols include brackets, braces, radical signs and absolute value bars. These are all included under the category of parentheses when performing order of operations. The Academic Support Center at Daytona State College (Math 17 pg 1 of 2) P E M D A S ( Please Excuse My Dear Aunt Sally ) Parentheses / Exponents ( ) Multiplication / Division Addition / Subtraction Parentheses Examples: [ ] Brackets { } Braces 2-8 4 6 =2-26 = 2 - 12 Radical Sign = -10 Check first for parentheses and / or exponents. Since there are none, you then looking for multiplication or division. Both operations are present, and because division comes first, going from left to right, you will do the division first (- 8 4). Multiplication comes next (-2 6), and then subtraction (2 - 12). 2. 32 + 7 - 5 (9 - 1) = 9 + 7 - 5 (8) = 9 + 7 - 40 = 16 - 40 = - 24 This problem has parentheses and an exponent. Since the exponent appears first, going from left to right, you must work it first ( 32). Next, you will do the arithmetic inside of the parentheses (9 - 1). The next operation to address is multiplication -5 (8). The parentheses in this situation signify multiplication. Addition precedes subtraction (9 + 7), then (16 - 40). 3. 4 + 2 [8 - (5 + 2)] = 4 + 2 [8 - (7)] = 4 + 2 (8 - 7) = 4 + 2 (1) =4+2 =6 Here we have parentheses within brackets. Start working the problem from the inside out; in other words, begin with the computation inside of the parentheses ( 5 + 2 ), then, remembering that there is an understood 1 by the parentheses - 1 ( 7 ), multiply to obtain - 7. Do the computation inside of the parentheses (8 - 7), and then follow with the next operation of importance, multiplication 2 (1). Finish up with the addition (4 + 2). 1. Absolute Value Bars Note: If you have parentheses within parentheses or brackets, work From the inside out. (See example 3) Caution! Do not attempt to do these problems in your head. Take the time to rewrite each step after completing an operation. JCM The Academic Support Center at Daytona State College (Math 17 pg 2 of 2)