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Simplify: ( x + 2 ) p .

xp + 2 p

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Simplify: ( y + 4 ) q .

yq + 4 q

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When you distribute a negative number, you need to be extra careful to get the signs correct.

Simplify: −2 ( 4 y + 1 ) .

Solution

.
Distribute. .
Simplify. .
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Simplify: −3 ( 6 m + 5 ) .

−18 m − 15

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Simplify: −6 ( 8 n + 11 ) .

−48 n − 66

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Simplify: −11 ( 4 3 a ) .

Solution

.
Distribute. .
Multiply. .
Simplify. .

You could also write the result as 33 a 44 . Do you know why?

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Simplify: −5 ( 2 3 a ) .

−10 + 15 a

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Simplify: −7 ( 8 15 y ) .

−56 + 105 y

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In the next example, we will show how to use the Distributive Property to find the opposite of an expression. Remember, a = −1 · a .

Simplify: ( y + 5 ) .

Solution

.
Multiplying by -1 results in the opposite. .
Distribute. .
Simplify. .
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Simplify: ( z 11 ) .

z + 11

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Simplify: ( x 4 ) .

x + 4

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Sometimes we need to use the Distributive Property as part of the order of operations. Start by looking at the parentheses. If the expression inside the parentheses cannot be simplified, the next step would be multiply using the distributive property, which removes the parentheses. The next two examples will illustrate this.

Simplify: 8 2 ( x + 3 ) .

Solution

.
Distribute. .
Multiply. .
Combine like terms. .
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Simplify: 9 3 ( x + 2 ) .

−3 x + 3

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Simplify: 7 x 5 ( x + 4 ) .

2 x − 20

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Simplify: 4 ( x 8 ) ( x + 3 ) .

Solution

.
Distribute. .
Combine like terms. .
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Simplify: 6 ( x 9 ) ( x + 12 ) .

5 x − 66

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Simplify: 8 ( x 1 ) ( x + 5 ) .

7 x − 13

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Evaluate expressions using the distributive property

Some students need to be convinced that the Distributive Property always works.

In the examples below, we will practice evaluating some of the expressions from previous examples; in part , we will evaluate the form with parentheses, and in part we will evaluate the form we got after distributing. If we evaluate both expressions correctly, this will show that they are indeed equal.

When y = 10 evaluate: 6 ( 5 y + 1 ) 6 · 5 y + 6 · 1 .

Solution

6 ( 5 y + 1 )
. .
Simplify in the parentheses. 6 ( 51 )
Multiply. 306
6 · 5 y + 6 · 1
. .
Simplify in the parentheses. .
Add. .

Notice, the answers are the same. When y = 10 ,

6 ( 5 y + 1 ) = 6 · 5 y + 6 · 1 .

Try it yourself for a different value of y .

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Evaluate when w = 3 : 5 ( 5 w + 9 ) 5 · 5 w + 5 · 9 .

  1. 120
  2. 120

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Evaluate when y = 2 : 9 ( 3 y + 8 ) 9 · 3 y + 9 · 8 .

  1. 126
  2. 126

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When y = 3 , evaluate −2 ( 4 y + 1 ) −2 · 4 y + ( −2 ) · 1 .

Solution

−2 ( 4 y + 1 )
. .
Simplify in the parentheses. −2 ( 13 )
Multiply. −26
−2 · 4 y + ( −2 ) · 1
. .
Multiply. −24 2
Subtract. −26
The answers are the same. When y = 3 , −2 ( 4 y + 1 ) = −8 y 2
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Evaluate when n = −2 : −6 ( 8 n + 11 ) −6 · 8 n + ( −6 ) · 11 .

  1. 30
  2. 30

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Evaluate when m = −1 : −3 ( 6 m + 5 ) −3 · 6 m + ( −3 ) · 5 .

  1. 3
  2. 3

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When y = 35 evaluate ( y + 5 ) and y 5 to show that ( y + 5 ) = y 5 .

Solution

( y + 5 )
. .
Add in the parentheses. - ( 40 )
Simplify. −40
y 5
. .
Simplify. −40
The answers are the same when y = 35 , demonstrating that ( y + 5 ) = y 5
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Evaluate when x = 36 : ( x 4 ) x + 4 to show that ( x 4 ) = x 4 .

  1. −32
  2. −32

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Evaluate when z = 55 : ( z 10 ) z + 10 to show that ( z 10 ) = z + 10 .

  1. −45
  2. −45

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Access additional online resources

Key concepts

  • Distributive Property:
    • If a , b , c are real numbers then
      • a ( b + c ) = a b + a c
      • ( b + c ) a = b a + c a
      • a ( b c ) = a b a c

Practice makes perfect

Simplify Expressions Using the Distributive Property

In the following exercises, simplify using the distributive property.

7 ( y 13 )

7 y − 91

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5 ( 7 u 4 )

35 u − 20

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1 5 ( 4 m + 20 )

4 5 m + 4

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10 ( 3 10 x 2 5 )

3 x − 4

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12 ( 1 6 + 3 4 s )

2 + 9 s

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u ( v 10 )

uv − 10 u

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−3 ( a + 11 )

−3 a − 33

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−9 ( 9 a + 4 )

−81 a − 36

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−4 ( q 7 )

−4 q + 28

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−6 ( 7 x 8 )

−42 x + 48

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( q + 11 )

q − 11

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( 5 p 4 )

−5 p + 4

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12 + 8 ( u 1 )

8 u + 4

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18 4 ( x + 2 )

−4 x + 10

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9 6 ( 7 n 5 )

−42 n + 39

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8 ( r 7 )

r + 15

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−4 ( c 10 )

c + 6

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( 5 m 3 ) ( m + 7 )

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( 4 y 1 ) ( y 2 )

3 y + 1

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5 ( 2 n + 9 ) + 12 ( n 3 )

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9 ( 5 u + 8 ) + 2 ( u 6 )

47 u + 60

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9 ( 8 x 3 ) ( −2 )

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4 ( 6 x 1 ) ( −8 )

24 x + 4

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14 ( c 1 ) 8 ( c 6 )

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11 ( n 7 ) 5 ( n 1 )

6 n − 72

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6 ( 7 y + 8 ) ( 30 y 15 )

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7 ( 3 n + 9 ) ( 4 n 13 )

17 n + 76

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Evaluate Expressions Using the Distributive Property

In the following exercises, evaluate both expressions for the given value.

If v = −2 , evaluate

  1. 6 ( 4 v + 7 )
  2. 6 · 4 v + 6 · 7

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If u = −1 , evaluate

  1. 8 ( 5 u + 12 )
  2. 8 · 5 u + 8 · 12

  1. 56
  2. 56

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If n = 2 3 , evaluate

  1. 3 ( n + 5 6 )
  2. 3 · n + 3 · 5 6

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If y = 3 4 , evaluate

  1. 4 ( y + 3 8 )
  2. 4 · y + 4 · 3 8

  1. 9 2
  2. 9 2

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If y = 7 12 , evaluate

  1. −3 ( 4 y + 15 )
  2. 3 · 4 y + ( −3 ) · 15

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If p = 23 30 , evaluate

  1. −6 ( 5 p + 11 )
  2. −6 · 5 p + ( −6 ) · 11

  1. −89
  2. −89

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If m = 0.4 , evaluate

  1. −10 ( 3 m 0.9 )
  2. −10 · 3 m ( −10 ) ( 0.9 )

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If n = 0.75 , evaluate

  1. −100 ( 5 n + 1.5 )
  2. −100 · 5 n + ( −100 ) ( 1.5 )

  1. −525
  2. −525

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If y = −25 , evaluate

  1. ( y 25 )
  2. y + 25

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If w = −80 , evaluate

  1. ( w 80 )
  2. w + 80

  1. 160
  2. 160

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If p = 0.19 , evaluate

  1. ( p + 0.72 )
  2. p 0.72

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If q = 0.55 , evaluate

  1. ( q + 0.48 )
  2. q 0.48

  1. −1.03
  2. −1.03

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Everyday math

Buying by the case Joe can buy his favorite ice tea at a convenience store for $1.99 per bottle. At the grocery store, he can buy a case of 12 bottles for $23.88 .

Use the distributive property to find the cost of 12 bottles bought individually at the convenience store. (Hint: notice that $1.99 is $2 $0.01 . )

Is it a bargain to buy the iced tea at the grocery store by the case?

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Multi-pack purchase Adele’s shampoo sells for $3.97 per bottle at the drug store. At the warehouse store, the same shampoo is sold as a 3-pack for $10.49 .

Show how you can use the distributive property to find the cost of 3 bottles bought individually at the drug store.

How much would Adele save by buying the 3-pack at the warehouse store?

  1. 3(4 − 0.03) = 11.91
  2. $1.42

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Writing exercises

Simplify 8 ( x 1 4 ) using the distributive property and explain each step.

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Explain how you can multiply 4 ( $5.97 ) without paper or a calculator by thinking of $5.97 as 6 0.03 and then using the distributive property.

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Self check

After completing the exercises, use this checklist to evaluate your mastery of the objectives of this section.

.

What does this checklist tell you about your mastery of this section? What steps will you take to improve?

Questions & Answers

A golfer on a fairway is 70 m away from the green, which sits below the level of the fairway by 20 m. If the golfer hits the ball at an angle of 40° with an initial speed of 20 m/s, how close to the green does she come?
Aislinn Reply
cm
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A mouse of mass 200 g falls 100 m down a vertical mine shaft and lands at the bottom with a speed of 8.0 m/s. During its fall, how much work is done on the mouse by air resistance
Jude Reply
Can you compute that for me. Ty
Jude
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what is viscosity?
David
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emma Reply
what is chemistry
Youesf Reply
what is inorganic
emma
Chemistry is a branch of science that deals with the study of matter,it composition,it structure and the changes it undergoes
Adjei
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Adjanou
chemistry could also be understood like the sexual attraction/repulsion of the male and female elements. the reaction varies depending on the energy differences of each given gender. + masculine -female.
Pedro
A ball is thrown straight up.it passes a 2.0m high window 7.50 m off the ground on it path up and takes 1.30 s to go past the window.what was the ball initial velocity
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2. A sled plus passenger with total mass 50 kg is pulled 20 m across the snow (0.20) at constant velocity by a force directed 25° above the horizontal. Calculate (a) the work of the applied force, (b) the work of friction, and (c) the total work.
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you have been hired as an espert witness in a court case involving an automobile accident. the accident involved car A of mass 1500kg which crashed into stationary car B of mass 1100kg. the driver of car A applied his brakes 15 m before he skidded and crashed into car B. after the collision, car A s
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can someone explain to me, an ignorant high school student, why the trend of the graph doesn't follow the fact that the higher frequency a sound wave is, the more power it is, hence, making me think the phons output would follow this general trend?
Joseph Reply
Nevermind i just realied that the graph is the phons output for a person with normal hearing and not just the phons output of the sound waves power, I should read the entire thing next time
Joseph
Follow up question, does anyone know where I can find a graph that accuretly depicts the actual relative "power" output of sound over its frequency instead of just humans hearing
Joseph
"Generation of electrical energy from sound energy | IEEE Conference Publication | IEEE Xplore" ***ieeexplore.ieee.org/document/7150687?reload=true
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Maurice
answer
Magreth
progressive wave
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hi
Mujahid
A string is 3.00 m long with a mass of 5.00 g. The string is held taut with a tension of 500.00 N applied to the string. A pulse is sent down the string. How long does it take the pulse to travel the 3.00 m of the string?
yasuo Reply
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Source:  OpenStax, Prealgebra. OpenStax CNX. Jul 15, 2016 Download for free at http://legacy.cnx.org/content/col11756/1.9
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