Simplifying Algebraic Fractions - Examples, Exercises and Solutions

When we have equal numbers or with a common denominator in the numerator and in the denominator, in certain cases, we can simplify fractions.

Often we will encounter an algebraic fraction in which the numerator and the denominator can be simplified. For example, this equation:

412x4\over12x

is a fraction that we can simplify. The simplification of algebraic fractions is a very important operation that will save us a lot of time when solving exercises and will help us avoid mistakes. In this article, we will learn when it is and is not allowed to simplify the numerator and the denominator.

Remember! Simplification between numerator and denominator is possible when the terms involve multiplication operations and there are no additions or subtractions.

Suggested Topics to Practice in Advance

  1. Factoring using contracted multiplication
  2. Factorization
  3. Extracting the common factor in parentheses
  4. Factorization: Common factor extraction
  5. Factoring Trinomials

Practice Simplifying Algebraic Fractions

Examples with solutions for Simplifying Algebraic Fractions

Exercise #1

Select the field of application of the following fraction:

8+x5 \frac{8+x}{5}

Video Solution

Step-by-Step Solution

Since the domain depends on the denominator, we note that there is no variable in the denominator.

Therefore, the domain is all numbers.

Answer

All numbers

Exercise #2

Select the field of application of the following fraction:

6x \frac{6}{x}

Video Solution

Step-by-Step Solution

Since the domain of definition depends on the denominator, and X appears in the denominator

All numbers will be suitable except for 0.

In other words, the domain of definition:

x0 x\ne0

Answer

All numbers except 0

Exercise #3

Determine if the simplification below is correct:

5883=53 \frac{5\cdot8}{8\cdot3}=\frac{5}{3}

Video Solution

Step-by-Step Solution

Let's consider the fraction and break it down into two multiplication exercises:

88×53 \frac{8}{8}\times\frac{5}{3}

We simplify:

1×53=53 1\times\frac{5}{3}=\frac{5}{3}

Answer

Correct

Exercise #4

Determine if the simplification shown below is correct:

778=8 \frac{7}{7\cdot8}=8

Video Solution

Step-by-Step Solution

Let's consider the fraction and break it down into two multiplication exercises:

77×18 \frac{7}{7}\times\frac{1}{8}

We simplify:

1×18=18 1\times\frac{1}{8}=\frac{1}{8}

Therefore, the described simplification is false.

Answer

Incorrect

Exercise #5

Determine if the simplification below is correct:

484=18 \frac{4\cdot8}{4}=\frac{1}{8}

Video Solution

Step-by-Step Solution

We will divide the fraction exercise into two multiplication exercises:

44×81= \frac{4}{4}\times\frac{8}{1}=

We simplify:

1×81=8 1\times\frac{8}{1}=8

Therefore, the described simplification is false.

Answer

Incorrect

Exercise #6

Determine if the simplification below is correct:

3773=0 \frac{3\cdot7}{7\cdot3}=0

Video Solution

Step-by-Step Solution

We will divide the fraction exercise into two different multiplication exercises.

As this is a multiplication exercise, you can use the substitution property:

77×33=1×1=1 \frac{7}{7}\times\frac{3}{3}=1\times1=1

Therefore, the simplification described is false.

Answer

Incorrect

Exercise #7

Determine if the simplification below is correct:

6363=1 \frac{6\cdot3}{6\cdot3}=1

Video Solution

Step-by-Step Solution

We simplify the expression on the left side of the approximate equality:

=?11=!1 \frac{\textcolor{red}{\not{6}}\cdot\textcolor{blue}{\not{3}}}{\textcolor{red}{\not{6}}\cdot\textcolor{blue}{\not{3}}}\stackrel{?}{= }1\\ \downarrow\\ 1\stackrel{!}{= }1 therefore, the described simplification is correct.

Therefore, the correct answer is A.

Answer

Correct

Exercise #8

Complete the corresponding expression for the denominator

16ab?=8a \frac{16ab}{?}=8a

Video Solution

Step-by-Step Solution

Using the formula:

xy=zwxy=zy \frac{x}{y}=\frac{z}{w}\xrightarrow{}x\cdot y=z\cdot y

We first convert the 8 into a fraction, and multiply

16ab?=81 \frac{16ab}{?}=\frac{8}{1}

16ab×1=8a 16ab\times1=8a

16ab=8a 16ab=8a

We then divide both sides by 8a:

16ab8a=8a8a \frac{16ab}{8a}=\frac{8a}{8a}

2b 2b

Answer

2b 2b

Exercise #9

Determine if the simplification described below is correct:

x+6y+6=xy \frac{x+6}{y+6}=\frac{x}{y}

Video Solution

Step-by-Step Solution

We use the formula:

x+zy+z=x+zy+z \frac{x+z}{y+z}=\frac{x+z}{y+z}

x+6y+6=x+6y+6 \frac{x+6}{y+6}=\frac{x+6}{y+6}

Therefore, the simplification described is incorrect.

Answer

Incorrect

Exercise #10

Determine if the simplification below is correct:

3xx+3=0 \frac{3-x}{-x+3}=0

Video Solution

Step-by-Step Solution

zxx+z=1 \frac{z-x}{-x+z}=1

Answer

Incorrect

Exercise #11

Indicate whether true or false

abca=cb \frac{a\cdot b}{c\cdot a}=\frac{c}{b}

Video Solution

Step-by-Step Solution

Let's examine the problem first:

abca=?cb \frac{a\cdot b}{c\cdot a} \stackrel{?}{= } \frac{c}{b} Note that we can simplify the expression on the left side, this can be done by reducing the fraction:

bc=bc \frac{\not{a}\cdot b}{c\cdot \not{a}} =\\ \boxed{\frac{b}{c}} However the expression on the right side is:

cb \frac{c}{b} Therefore the expressions on both sides of the (assumed) equation are not equal, meaning:

abca=bc!cb \frac{a\cdot b}{c\cdot a}=\frac{b}{c} \stackrel{!}{\neq } \frac{c}{b}

(In other words, there is no identity equation- which is true for all possible parameter values a,b,c a,b,c )

Therefore the correct answer is answer B.

Answer

Not true

Exercise #12

Indicate whether true or false

caac=0 \frac{c\cdot a}{a\cdot c}=0

Video Solution

Step-by-Step Solution

Let's simplify the expression on the left side of the proposed equation:

=?01=?0 \frac{\not{c}\cdot \not{a}}{\not{a}\cdot \not{c}}\stackrel{?}{= }0 \\ 1 \stackrel{?}{= }0 Clearly, we get a false statement because: 1 is different from: 0

1!0 \boxed{ 1 \stackrel{!}{\neq }0} Therefore, the proposed equation is not correct,

Which means the correct answer is answer B.

Answer

Not true

Exercise #13

Determine if the simplification below is correct:

3483=12 \frac{3\cdot4}{8\cdot3}=\frac{1}{2}

Video Solution

Step-by-Step Solution

We simplify the expression on the left side of the approximate equality.

First let's consider the fact that the number 8 is a multiple of the number 4:

8=24 8=2\cdot4
Therefore, we will return to the problem in question and present the number 8 as a multiple of the number 4, then we will simplify the fraction:

3483=?1234243=?122=?1212=!12 \frac{3\cdot4}{\underline{8}\cdot3}\stackrel{?}{= }\frac{1}{2}\\ \downarrow\\ \frac{3\cdot4}{\underline{2\cdot4}\cdot3}\stackrel{?}{= }\frac{1}{2}\\ \downarrow\\ \frac{\textcolor{blue}{\not{3}}\cdot\textcolor{red}{\not{4}}}{2\cdot\textcolor{red}{\not{4}}\cdot\textcolor{blue}{\not{3}}}\stackrel{?}{= }\frac{1}{2} \\ \downarrow\\ \frac{1}{2}\stackrel{!}{= }\frac{1}{2}
Therefore, the described simplification is correct.

That is, the correct answer is A.

Answer

True

Exercise #14

Simplify:

5x215xx3 \frac{5x^2-15x}{x-3}

Video Solution

Step-by-Step Solution

Let's simplify the given expression:

5x215xx3 \frac{5x^2-15x}{x-3} Remember that we can reduce complete expressions only when both the numerator and denominator are completely factored into multiplication expressions,

For this, we'll use factorization, identify that in the numerator we can factor out a common term, do this, then reduce the expressions possible in the fraction we got (reduction sign):

5x215xx35x(x3)x35x \frac{5x^2-15x}{x-3} \\ \frac{5x(x-3)}{x-3} \\ \downarrow\\ \boxed{5x} Therefore, the correct answer is answer B.

Answer

5x 5x

Exercise #15

Simplify:

16x4x24x \frac{16x-4x^2}{4-x}

Video Solution

Step-by-Step Solution

Let's simplify the given expression:

16x4x24x \frac{16x-4x^2}{4-x} Remember that we can reduce complete expressions only when both the numerator and denominator are completely factored into multiplication expressions,

For this, we'll use factorization, identify that in the numerator we can factor out a common term, do this, then reduce the expressions possible in the fraction we got (reduction sign):

16x4x24x4x(x4)x44x \frac{16x-4x^2}{4-x} \\ \frac{4x(x-4)}{x-4} \\ \downarrow\\ \boxed{4x} Therefore, the correct answer is answer B.

Answer

4x 4x

Topics learned in later sections

  1. Algebraic Fractions
  2. Factoring Algebraic Fractions
  3. Addition and Subtraction of Algebraic Fractions
  4. Multiplication and Division of Algebraic Fractions
  5. Solving Equations by Factoring
  6. Uses of Factorization