<< Chapter < Page Chapter >> Page >
By the end of this section, you will be able to:
  • Simplify expressions with exponents
  • Simplify expressions using the Product Property for Exponents
  • Simplify expressions using the Power Property for Exponents
  • Simplify expressions using the Product to a Power Property
  • Simplify expressions by applying several properties
  • Multiply monomials

Before you get started, take this readiness quiz.

  1. Simplify: 3 4 · 3 4 .
    If you missed this problem, review [link] .
  2. Simplify: ( −2 ) ( −2 ) ( −2 ) .
    If you missed this problem, review [link] .

Simplify expressions with exponents

Remember that an exponent indicates repeated multiplication of the same quantity. For example, 2 4 means to multiply 2 by itself 4 times, so 2 4 means 2 · 2 · 2 · 2 .

Let’s review the vocabulary for expressions with exponents.

Exponential notation

This figure has two columns. In the left column is a to the m power. The m is labeled in blue as an exponent. The a is labeled in red as the base. In the right column is the text “a to the m power means multiply m factors of a.” Below this is a to the m power equals a times a times a times a, followed by an ellipsis, with “m factors” written below in blue.

This is read a to the m t h power.

In the expression a m , the exponent m tells us how many times we use the base a as a factor.

This figure has two columns. The left column contains 4 cubed. Below this is 4 times 4 times 4, with “3 factors” written below in blue. The right column contains negative 9 to the fifth power. Below this is negative 9 times negative 9 times negative 9 times negative 9 times negative 9, with “5 factors” written below in blue.

Before we begin working with variable expressions containing exponents, let’s simplify a few expressions involving only numbers.

Simplify: 4 3 7 1 ( 5 6 ) 2 ( 0.63 ) 2 .

Solution


4 3 Multiply three factors of 4. 4 · 4 · 4 Simplify. 64


7 1 Multiply one factor of 7. 7


( 5 6 ) 2 Multiply two factors. ( 5 6 ) ( 5 6 ) Simplify. 25 36


( 0.63 ) 2 Multiply two factors. ( 0.63 ) ( 0.63 ) Simplify. 0.3969

Got questions? Get instant answers now!
Got questions? Get instant answers now!

Simplify: 6 3 15 1 ( 3 7 ) 2 ( 0.43 ) 2 .

216 15 9 49 0.1849

Got questions? Get instant answers now!

Simplify: 2 5 21 1 ( 2 5 ) 3 ( 0.218 ) 2 .

32 21 8 125 0.047524

Got questions? Get instant answers now!

Simplify: ( −5 ) 4 5 4 .

Solution


  1. ( −5 ) 4 Multiply four factors of −5 . ( −5 ) ( −5 ) ( −5 ) ( −5 ) Simplify. 625


  2. 5 4 Multiply four factors of 5. ( 5 · 5 · 5 · 5 ) Simplify. −625
Got questions? Get instant answers now!
Got questions? Get instant answers now!

Simplify: ( −3 ) 4 3 4 .

81 −81

Got questions? Get instant answers now!

Simplify: ( −13 ) 2 13 2 .

169 −169

Got questions? Get instant answers now!

Notice the similarities and differences in [link] and [link] ! Why are the answers different? As we follow the order of operations in part the parentheses tell us to raise the ( −5 ) to the 4 th power. In part we raise just the 5 to the 4 th power and then take the opposite.

Simplify expressions using the product property for exponents

You have seen that when you combine like terms by adding and subtracting, you need to have the same base with the same exponent. But when you multiply and divide, the exponents may be different, and sometimes the bases may be different, too.

We’ll derive the properties of exponents by looking for patterns in several examples.

First, we will look at an example that leads to the Product Property.

x squared times x cubed.
What does this mean?
How many factors altogether?
x times x, multiplied by x times x. x times x has two factors. x times x times x has three factors. 2 plus 3 is five factors.
So, we have x to the fifth power.
Notice that 5 is the sum of the exponents, 2 and 3. x squared times x cubed is x to the power of 2 plus 3, or x to the fifth power.

We write:

x 2 · x 3 x 2 + 3 x 5

The base stayed the same and we added the exponents. This leads to the Product Property for Exponents .

Product property for exponents

If a is a real number, and m and n are counting numbers, then

a m · a n = a m + n

To multiply with like bases, add the exponents.

An example with numbers helps to verify this property.

2 2 · 2 3 = ? 2 2 + 3 4 · 8 = ? 2 5 32 = 32

Simplify: y 5 · y 6 .

Solution

y to the fifth power times y to the sixth power.
Use the product property, a m · a n = a m+n . y to the power of 5 plus 6.
Simplify. y to the eleventh power.

Got questions? Get instant answers now!
Got questions? Get instant answers now!

Simplify: b 9 · b 8 .

b 17

Got questions? Get instant answers now!

Simplify: x 12 · x 4 .

x 16

Got questions? Get instant answers now!

Simplify: 2 5 · 2 9 3 · 3 4 .

Solution


  1. 2 to the fifth power times 2 to the ninth power.
    Use the product property, a m · a n = a m+n . 2 to the power of 5 plus 9.
    Simplify. 2 to the 14th power.

  2. 3 to the fifth power times 3 to the fourth power.
    Use the product property, a m · a n = a m+n . 3 to the power of 5 plus 4.
    Simplify. 3 to the ninth power.
Got questions? Get instant answers now!
Got questions? Get instant answers now!

Simplify: 5 · 5 5 4 9 · 4 9 .

5 6 4 18

Got questions? Get instant answers now!

Simplify: 7 6 · 7 8 10 · 10 10 .

7 14 10 11

Got questions? Get instant answers now!

Simplify: a 7 · a x 27 · x 13 .

Solution


  1. a to the seventh power times a.
    Rewrite, a = a 1 . a to the seventh power times a to the first power.
    Use the product property, a m · a n = a m+n . a to the power of 7 plus 1.
    Simplify. a to the eighth power.

  2. x to the twenty-seventh power times x to the thirteenth power.
    Notice, the bases are the same, so add the exponents. x to the power of 27 plus 13.
    Simplify. x to the fortieth power.
Got questions? Get instant answers now!
Got questions? Get instant answers now!

Questions & Answers

how did you get 1640
Noor Reply
If auger is pair are the roots of equation x2+5x-3=0
Peter Reply
Wayne and Dennis like to ride the bike path from Riverside Park to the beach. Dennis’s speed is seven miles per hour faster than Wayne’s speed, so it takes Wayne 2 hours to ride to the beach while it takes Dennis 1.5 hours for the ride. Find the speed of both bikers.
MATTHEW Reply
420
Sharon
from theory: distance [miles] = speed [mph] × time [hours] info #1 speed_Dennis × 1.5 = speed_Wayne × 2 => speed_Wayne = 0.75 × speed_Dennis (i) info #2 speed_Dennis = speed_Wayne + 7 [mph] (ii) use (i) in (ii) => [...] speed_Dennis = 28 mph speed_Wayne = 21 mph
George
Let W be Wayne's speed in miles per hour and D be Dennis's speed in miles per hour. We know that W + 7 = D and W * 2 = D * 1.5. Substituting the first equation into the second: W * 2 = (W + 7) * 1.5 W * 2 = W * 1.5 + 7 * 1.5 0.5 * W = 7 * 1.5 W = 7 * 3 or 21 W is 21 D = W + 7 D = 21 + 7 D = 28
Salma
Devon is 32 32​​ years older than his son, Milan. The sum of both their ages is 54 54​. Using the variables d d​ and m m​ to represent the ages of Devon and Milan, respectively, write a system of equations to describe this situation. Enter the equations below, separated by a comma.
Aaron Reply
find product (-6m+6) ( 3m²+4m-3)
SIMRAN Reply
-42m²+60m-18
Salma
what is the solution
bill
how did you arrive at this answer?
bill
-24m+3+3mÁ^2
Susan
i really want to learn
Amira
I only got 42 the rest i don't know how to solve it. Please i need help from anyone to help me improve my solving mathematics please
Amira
Hw did u arrive to this answer.
Aphelele
hi
Bajemah
-6m(3mA²+4m-3)+6(3mA²+4m-3) =-18m²A²-24m²+18m+18mA²+24m-18 Rearrange like items -18m²A²-24m²+42m+18A²-18
Salma
complete the table of valuesfor each given equatio then graph. 1.x+2y=3
Jovelyn Reply
x=3-2y
Salma
y=x+3/2
Salma
Hi
Enock
given that (7x-5):(2+4x)=8:7find the value of x
Nandala
3x-12y=18
Kelvin
please why isn't that the 0is in ten thousand place
Grace Reply
please why is it that the 0is in the place of ten thousand
Grace
Send the example to me here and let me see
Stephen
A meditation garden is in the shape of a right triangle, with one leg 7 feet. The length of the hypotenuse is one more than the length of one of the other legs. Find the lengths of the hypotenuse and the other leg
Marry Reply
how far
Abubakar
cool u
Enock
state in which quadrant or on which axis each of the following angles given measure. in standard position would lie 89°
Abegail Reply
hello
BenJay
hi
Method
I am eliacin, I need your help in maths
Rood
how can I help
Sir
hmm can we speak here?
Amoon
however, may I ask you some questions about Algarba?
Amoon
hi
Enock
what the last part of the problem mean?
Roger
The Jones family took a 15 mile canoe ride down the Indian River in three hours. After lunch, the return trip back up the river took five hours. Find the rate, in mph, of the canoe in still water and the rate of the current.
cameron Reply
Shakir works at a computer store. His weekly pay will be either a fixed amount, $925, or $500 plus 12% of his total sales. How much should his total sales be for his variable pay option to exceed the fixed amount of $925.
mahnoor Reply
I'm guessing, but it's somewhere around $4335.00 I think
Lewis
12% of sales will need to exceed 925 - 500, or 425 to exceed fixed amount option. What amount of sales does that equal? 425 ÷ (12÷100) = 3541.67. So the answer is sales greater than 3541.67. Check: Sales = 3542 Commission 12%=425.04 Pay = 500 + 425.04 = 925.04. 925.04 > 925.00
Munster
difference between rational and irrational numbers
Arundhati Reply
When traveling to Great Britain, Bethany exchanged $602 US dollars into £515 British pounds. How many pounds did she receive for each US dollar?
Jakoiya Reply
how to reduced echelon form
Solomon Reply
Jazmine trained for 3 hours on Saturday. She ran 8 miles and then biked 24 miles. Her biking speed is 4 mph faster than her running speed. What is her running speed?
Zack Reply
d=r×t the equation would be 8/r+24/r+4=3 worked out
Sheirtina

Get Jobilize Job Search Mobile App in your pocket Now!

Get it on Google Play Download on the App Store Now




Source:  OpenStax, Elementary algebra. OpenStax CNX. Jan 18, 2017 Download for free at http://cnx.org/content/col12116/1.2
Google Play and the Google Play logo are trademarks of Google Inc.

Notification Switch

Would you like to follow the 'Elementary algebra' conversation and receive update notifications?

Ask