Exercise 22 Page 325

According to the order of operations, expressions inside parentheses are evaluated first, followed by exponents, then multiplication and division, and finally addition and subtraction are evaluated last. We can use the acronym PEMDAS to help us remember the correct order!

We want to simplify the given expression.

7-9÷ 9+4(4-3)-7 The first step is evaluate the expression inside the parentheses. 7-9÷ 9+4(4-3)-7 → 7-9÷ 9+4(1)-7 Now, we will follow the order of operations.

Operation	Before Simplification	After Simplification
Multiply	7-9÷ 9+ 4( 1)-7	7-9÷ 9+ 4-7
Divide	7- 9÷ 9+4-7	7-1+4-7
Add terms	7- 1+ 4-7	7- 5-7
Subtract terms	7- 5- 7	- 5

The expression is equal to - 5.

According to the order of operations, expressions inside parentheses are evaluated first, followed by exponents, then multiplication and division, and finally addition and subtraction are evaluated last. We can use the acronym PEMDAS to help us remember the correct order!

We want to simplify the given expression.

- 12 +3(7-4)+5 The first step is evaluate the expression inside the parentheses. - 12 +3(7-4)+5 → - 12 +3(3)+5 Now, we will follow the order of operations.

Operation	Before Simplification	After Simplification
Multiply	- 12 + 3( 3)+5	- 12 + 9+5
Add terms	- 12 + 9+ 5	2

The expression is equal to 2.

According to the order of operations, expressions inside parentheses are evaluated first, followed by exponents, then multiplication and division, and finally addition and subtraction are evaluated last. We can use the acronym PEMDAS to help us remember the correct order!

We want to simplify the given expression. For the given expression, this means evaluating the expression inside the parentheses completely before adding the product.

3(15-2* 6)-5 Notice also that even within this parenthetical expression, we must follow the order of operations. 15-2* 6 Let's do it!

Operation	Before Simplification	After Simplification
Multiply	3(15- 2* 6)-5	3(15- 12)-5
Subtract terms	3( 15- 12)-5	3( 3)-5
Multiply	3( 3)-5	9-5
Subtract terms	9- 5	4

The expression is equal to 4.