Order of Operations

Order of Operations

Objective: To recognize which operations have priority when solving problems

What we have done so far...

Previously we computed problems that only required us to complete one step. For example, 
 $10-5$   
We computed by performing the addition of the opposite of 5, so  $10+-5$  and we would get, 
 $5$  

Multiple Select

Solve this expression,

 $2-10$  

• -12

• -8

• 12

• 8

Order of Operations

In this section are some simplifying problems that take more than one step - so we have to figure out what to do first.

"Operations" mean things like add, subtract, multiply, divide, squaring, etc.

So when you see something like ...

7 + (6 × 5 + 3)

... what part should we calculate first?

Multiple Choice

 $7+\left(6\times5+3\right)$  

Try solving this with a calculator, what do you get?

• 42

• 68

• 54

• 40

How did we all do?

Multiple people got different answers, this is because the ORDER in which we solve these multi-step problems is important to making sure we have the correct answer! The order we must solve is as easy as popcorn every monday, donuts every sunday. PEMDAS

PEMDAS

P Parentheses first

E Exponents (ie Powers and Square Roots, etc.)

M Multiplication and

D Division (left-to-right)

A Addition and

S Subtraction (left-to-right)

PEMDAS

• Pudgy Elves May Demand A Snack

• Please Excuse My Dear Aunt Sally

• People Everywhere Made Decisions About Sums

• Please Eat Mom's Delicious Apple Strudels

Multiple Select

Which saying do you think is best to remember PEMDAS?

• Please Eat Mom's Delicious Apple Strudels

• Please Excuse My Dear Aunt Sally

• Pudgy Elves May Demand A Snack

• People Everywhere Made Decisions About Sums 123

Examples

A.  $3+6\times2$  
Multiplication before Addition
First,  $6\times2=12$  , then  $3+12=15$  

B.  $\left(3+6\right)\times2$  
Parenthesis before Multiplication 
First,  $3+6=9$  , then  $9\times2=18$  
C.  $6\div3+4\times2$  
Multiplication/Division before Addition (left to right)
First,  $6\div3=2$ , second  $4\times2=8$ , then 
 $2+8=10$ 

Multiple Choice

 $7+\left(6\times5+3\right)$  

Remember our problem from earlier? Try solving it now that you know PEMDAS.

• 32

• 40

• 27

• 38

Poll

How confident do you feel about today's lesson?

• 25%

• 50%

• 75%

• 100%

Next Time:

We will use PEMDAS to solve expressions! Think about this for next class, what order would I solve this expression?

 $5x-\left(4x-x\right)$  

Independent Work Time

For the remainder of class please work on your assignment titled "PEMAS" in google classroom. You are welcome to ask questions while you are working. If you finish EARLY with ABOVE an 80% you may leave after you wave goodbye :)