Can you figure it out? Warm Up Copy down your homework: Order of Operations Worksheet Can you figure it out?
6 ÷ 2(1 + 2) Karen got 1 and Steven got 9. I wonder who is correct. Which do you agree with? We will reveal the answer at the end of todays lesson
Today’s Lesson: Order of Operations September 1st, 2016
Today I will be teaching you how to use the Order of Operation.
First lets take a Quiz! Solve: 2 + 3(4 – 5)² ÷ 3
Wrong! Solve: 2 + 3(4-5)²÷ 3 2+3= 5(4-5)²÷3 5x4= 20-5²÷3 20-5²=-5÷3 Answer : -5/3 Wrong!
What Is Order of Operations?
What is the Order in Order of Operations?
P. E.M.D.A.S
Copy this on a sheet of paper for your notes
How can I remember the order of P.E.M.D.A.S. ?
Please Excuse My Dear Aunt Sally!
The in P.E.M.D.A.S. stands for Parenthesis. This is the first thing you should look for in working out the problem. Sometimes you may have other grouping symbols.
Grouping symbols If there is more than one grouping symbol, work from the innermost symbols first
Example Which grouping symbol do you work from first?
The in P.E.M.D.A.S. stands for Exponents. This is the second procedure you should take in working out the problem. Ex. 2+3(4-5)²÷3 (-1)²= 1
The and the in P.E.M.D.A.S. stands for Multiplication and Division. In solving the problem you would work these after the exponents but from left to right. Ex. 2+3(4-5)²÷3 3×1=3 3÷3=1
The and the in P.E.M.D.A.S. stand for Addition and Subtraction. Like multiplication and division you would work these from left to right as they appear in the problem. Ex. 2+3(4-5)²÷3 2+1=3
Now lets try it again!
Correct! Solve: 2+3(4-5)²÷3 P:(4-5)=-1 2+3(-1)²÷3 E:(-1)²= 1 2+3x1÷3 M:3x1= 3 2+3÷3 D: 3÷3=1 2+1 A: 2+1= 3 S: None Answer: 3 Correct!
Let’s work it out! 6 ÷ 2(1 + 2)
You try Answer: 7
You try Answer: 17
You try Answer: 9
You try Answer: 26
You try Answer: -4
You try Answer: 9
means the opposite of the square of x and will always be a negative answer means the opposite of x squared, which will always be a positive answer
Calculator If using a calculator, you MUST put parentheses around a negative number if the number has an exponent
Let’s end the day with something new!
Evaluating Expressions Evaluate the following expressions if a = 2, b = -3, c = 1 Answer: 11 Answer: -5