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Using the order of operations

Use the order of operations to evaluate each of the following expressions.

  1. ( 3 2 ) 2 4 ( 6 + 2 )
  2. 5 2 4 7 11 2
  3. 6 | 5 8 | + 3 ( 4 1 )
  4. 14 3 2 2 5 3 2
  5. 7 ( 5 3 ) 2 [ ( 6 3 ) 4 2 ] + 1

  1. ( 3 2 ) 2 4 ( 6 + 2 ) = ( 6 ) 2 4 ( 8 ) Simplify parentheses = 36 4 ( 8 ) Simplify exponent = 36 32 Simplify multiplication = 4 Simplify subtraction

  2. 5 2 4 7 11 2 = 5 2 4 7 9 Simplify grouping symbols (radical) = 5 2 4 7 3 Simplify radical = 25 4 7 3 Simplify exponent = 21 7 3 Simplify subtraction in numerator = 3 3 Simplify division = 0 Simplify subtraction

    Note that in the first step, the radical is treated as a grouping symbol, like parentheses. Also, in the third step, the fraction bar is considered a grouping symbol so the numerator is considered to be grouped.


  3. 6 | 5 8 | + 3 ( 4 1 ) = 6 | −3 | + 3 ( 3 ) Simplify inside grouping symbols = 6 3 + 3 ( 3 ) Simplify absolute value = 6 3 + 9 Simplify multiplication = 3 + 9 Simplify subtraction = 12 Simplify addition

  4. 14 3 2 2 5 3 2 = 14 3 2 2 5 9 Simplify exponent = 14 6 10 9 Simplify products = 8 1 Simplify differences = 8 Simplify quotient

    In this example, the fraction bar separates the numerator and denominator, which we simplify separately until the last step.


  5. 7 ( 5 3 ) 2 [ ( 6 3 ) 4 2 ] + 1 = 7 ( 15 ) 2 [ ( 3 ) 4 2 ] + 1 Simplify inside parentheses = 7 ( 15 ) 2 ( 3 16 ) + 1 Simplify exponent = 7 ( 15 ) 2 ( −13 ) + 1 Subtract = 105 + 26 + 1 Multiply = 132 Add
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Use the order of operations to evaluate each of the following expressions.

  1. 5 2 4 2 + 7 ( 5 4 ) 2
  2. 1 + 7 5 8 4 9 6
  3. | 1.8 4.3 | + 0.4 15 + 10
  4. 1 2 [ 5 3 2 7 2 ] + 1 3 9 2
  5. [ ( 3 8 ) 2 4 ] ( 3 8 )
  1. 10
  2. 2
  3. 4.5
  4. 25
  5. 26
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Using properties of real numbers

For some activities we perform, the order of certain operations does not matter, but the order of other operations does. For example, it does not make a difference if we put on the right shoe before the left or vice-versa. However, it does matter whether we put on shoes or socks first. The same thing is true for operations in mathematics.

Commutative properties

The commutative property of addition    states that numbers may be added in any order without affecting the sum.

a + b = b + a

We can better see this relationship when using real numbers.

( −2 ) + 7 = 5 and 7 + ( −2 ) = 5

Similarly, the commutative property of multiplication    states that numbers may be multiplied in any order without affecting the product.

a b = b a

Again, consider an example with real numbers.

( −11 ) ( −4 ) = 44 and ( −4 ) ( −11 ) = 44

It is important to note that neither subtraction nor division is commutative. For example, 17 5 is not the same as 5 17. Similarly, 20 ÷ 5 5 ÷ 20.

Associative properties

The associative property of multiplication    tells us that it does not matter how we group numbers when multiplying. We can move the grouping symbols to make the calculation easier, and the product remains the same.

a ( b c ) = ( a b ) c

Consider this example.

( 3 4 ) 5 = 60 and 3 ( 4 5 ) = 60

The associative property of addition    tells us that numbers may be grouped differently without affecting the sum.

a + ( b + c ) = ( a + b ) + c

This property can be especially helpful when dealing with negative integers. Consider this example.

[ 15 + ( −9 ) ] + 23 = 29 and 15 + [ ( −9 ) + 23 ] = 29

Are subtraction and division associative? Review these examples.

8 ( 3 15 ) = ? ( 8 3 ) 15 64 ÷ ( 8 ÷ 4 ) = ? ( 64 ÷ 8 ) ÷ 4 8 ( 12 ) = 5 15   64 ÷ 2 = ?   8 ÷ 4 20   20 10   32 2

Questions & Answers

if sin15°=√p, express the following in terms of p
Norman Reply
prove sin²x+cos²x=3+cos4x
Kiddy Reply
the difference between two signed numbers is -8.if the minued is 5,what is the subtrahend
jeramie Reply
the difference between two signed numbers is -8.if the minuend is 5.what is the subtrahend
jeramie
what are odd numbers
micheal Reply
numbers that leave a remainder when divided by 2
Thorben
1,3,5,7,... 99,...867
Thorben
7%2=1, 679%2=1, 866245%2=1
Thorben
the third and the seventh terms of a G.P are 81 and 16, find the first and fifth terms.
Suleiman Reply
if a=3, b =4 and c=5 find the six trigonometric value sin
Martin Reply
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Ans
pls how do I factorize x⁴+x³-7x²-x+6=0
Gift Reply
in a function the input value is called
Rimsha Reply
how do I test for values on the number line
Modesta Reply
if a=4 b=4 then a+b=
Rimsha Reply
a+b+2ab
Kin
commulative principle
DIOSDADO
a+b= 4+4=8
Mimi
If a=4 and b=4 then we add the value of a and b i.e a+b=4+4=8.
Tariq
what are examples of natural number
sani Reply
an equation for the line that goes through the point (-1,12) and has a slope of 2,3
Katheryn Reply
3y=-9x+25
Ishaq
show that the set of natural numberdoes not from agroup with addition or multiplication butit forms aseni group with respect toaaddition as well as multiplication
Komal Reply
x^20+x^15+x^10+x^5/x^2+1
Urmila Reply
evaluate each algebraic expression. 2x+×_2 if ×=5
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Source:  OpenStax, Algebra and trigonometry. OpenStax CNX. Nov 14, 2016 Download for free at https://legacy.cnx.org/content/col11758/1.6
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