Adding and Subtracting Rational Expressions - Algebra 2
Card 1 of 228
Subtract the following expressions: 
Subtract the following expressions:
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In order to subtract the fractions, multiply both denominators together in order to obtain the least common denominator.

Simplify the numerators.

Combine the numerators.

The answer is: 
In order to subtract the fractions, multiply both denominators together in order to obtain the least common denominator.
Simplify the numerators.
Combine the numerators.
The answer is:
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Determine the value of
.
Determine the value of .
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(x+5)(x+3) is the common denominator for this problem making the numerators 7(x+3) and 8(x+5).
7(x+3)+8(x+5)= 7x+21+8x+40= 15x+61
A=61
(x+5)(x+3) is the common denominator for this problem making the numerators 7(x+3) and 8(x+5).
7(x+3)+8(x+5)= 7x+21+8x+40= 15x+61
A=61
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Solve: 
Solve:
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To simplify this expression, we will need to multiply both denominators together to find the least common denominator.

Convert both fractions to the common denominator.


Combine the fractions.

The answer is: 
To simplify this expression, we will need to multiply both denominators together to find the least common denominator.
Convert both fractions to the common denominator.
Combine the fractions.
The answer is:
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Simplify: 
Simplify:
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First, simplify the expression before attempting to combine like-terms.


Combine like-terms.

First, simplify the expression before attempting to combine like-terms.
Combine like-terms.
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Simplify. 
Simplify.
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The values can only be added or subtracted if there are like-terms in the expression. Since there are no like-terms in the question, the question is already simplified as is. All the other answers given are incorrect.
The values can only be added or subtracted if there are like-terms in the expression. Since there are no like-terms in the question, the question is already simplified as is. All the other answers given are incorrect.
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Simplify:

Simplify:
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Because the two rational expressions have the same denominator, we can simply add straight across the top. The denominator stays the same.
Therefore the answer is
.
Because the two rational expressions have the same denominator, we can simply add straight across the top. The denominator stays the same.
Therefore the answer is .
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Simplify the rational expression: 
Simplify the rational expression:
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There are multiple operations required in this problem. The exponent must be eliminated before distributing the negative sign. Use the FOIL method which means to mulitply the first terms together, then multiply the outer terms together, then multiply the inner terms togethers, and lastly, mulitply the last terms together.

![= -[(-2x+3)(-2x+3)]](https://vt-vtwa-assets.varsitytutors.com/vt-vtwa/uploads/formula_image/image/391492/gif.latex)
![=-[(-2x)(-2x)+(-2x)(3)+(3)(-2x)+(3)(3)]](https://vt-vtwa-assets.varsitytutors.com/vt-vtwa/uploads/formula_image/image/391493/gif.latex)


The negative sign can now be distributed.

There are multiple operations required in this problem. The exponent must be eliminated before distributing the negative sign. Use the FOIL method which means to mulitply the first terms together, then multiply the outer terms together, then multiply the inner terms togethers, and lastly, mulitply the last terms together.
The negative sign can now be distributed.
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Add:

Add:
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First factor the denominators which gives us the following:

The two rational fractions have a common denominator hence they are like "like fractions". Hence we get:

Simplifying gives us

First factor the denominators which gives us the following:
The two rational fractions have a common denominator hence they are like "like fractions". Hence we get:
Simplifying gives us
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Subtract:

Subtract:
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First let us find a common denominator as follows:

Now we can subtract the numerators which gives us : 
So the final answer is 
First let us find a common denominator as follows:
Now we can subtract the numerators which gives us :
So the final answer is
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Simplify 
Simplify
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This is a more complicated form of 
Find the least common denominator (LCD) and convert each fraction to the LCD, then add the numerators. Simplify as needed.

which is equivalent to 
Simplify to get 
This is a more complicated form of
Find the least common denominator (LCD) and convert each fraction to the LCD, then add the numerators. Simplify as needed.
which is equivalent to
Simplify to get
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Solve the rational equation:

Solve the rational equation:
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With rational equations we must first note the domain, which is all real numbers except
. (Recall, the denominator cannot equal zero. Thus, to find the domain set each denominator equal to zero and solve for what the variable cannot be.)
The least common denominator or
and
is
. Multiply every term by the LCD to cancel out the denominators. The equation reduces to
. We can FOIL to expand the equation to
. Combine like terms and solve:
. Factor the quadratic and set each factor equal to zero to obtain the solution, which is
or
. These answers are valid because they are in the domain.
With rational equations we must first note the domain, which is all real numbers except . (Recall, the denominator cannot equal zero. Thus, to find the domain set each denominator equal to zero and solve for what the variable cannot be.)
The least common denominator or and
is
. Multiply every term by the LCD to cancel out the denominators. The equation reduces to
. We can FOIL to expand the equation to
. Combine like terms and solve:
. Factor the quadratic and set each factor equal to zero to obtain the solution, which is
or
. These answers are valid because they are in the domain.
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Simplify

Simplify
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a. Find a common denominator by identifying the Least Common Multiple of both denominators. The LCM of 3 and 1 is 3. The LCM of
and
is
. Therefore, the common denominator is
.
b. Write an equivialent fraction to
using
as the denominator. Multiply both the numerator and the denominator by
to get
. Notice that the second fraction in the original expression already has
as a denominator, so it does not need to be converted.
The expression should now look like:
.
c. Subtract the numerators, putting the difference over the common denominator.

a. Find a common denominator by identifying the Least Common Multiple of both denominators. The LCM of 3 and 1 is 3. The LCM of and
is
. Therefore, the common denominator is
.
b. Write an equivialent fraction to using
as the denominator. Multiply both the numerator and the denominator by
to get
. Notice that the second fraction in the original expression already has
as a denominator, so it does not need to be converted.
The expression should now look like: .
c. Subtract the numerators, putting the difference over the common denominator.
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Combine the following expression into one fraction:

Combine the following expression into one fraction:
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To combine fractions of different denominators, we must first find a common denominator between the two. We can do this by multiplying the first fraction by
and the second fraction by
. We therefore obtain:


Since these fractions have the same denominators, we can now combine them, and our final answer is therefore:

To combine fractions of different denominators, we must first find a common denominator between the two. We can do this by multiplying the first fraction by and the second fraction by
. We therefore obtain:
Since these fractions have the same denominators, we can now combine them, and our final answer is therefore:
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What is
?
What is ?
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We start by adjusting both terms to the same denominator which is 2 x 3 = 6
Then we adjust the numerators by multiplying x+1 by 2 and 2x-5 by 3

The results are:

So the final answer is,

We start by adjusting both terms to the same denominator which is 2 x 3 = 6
Then we adjust the numerators by multiplying x+1 by 2 and 2x-5 by 3
The results are:
So the final answer is,
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What is
?
What is ?
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Start by putting both equations at the same denominator.
2x+4 = (x+2) x 2 so we only need to adjust the first term:


Then we subtract the numerators, remembering to distribute the negative sign to all terms of the second fraction's numerator:

Start by putting both equations at the same denominator.
2x+4 = (x+2) x 2 so we only need to adjust the first term:
Then we subtract the numerators, remembering to distribute the negative sign to all terms of the second fraction's numerator:
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First, find the common denominator, which is
. Then, make sure to offset each numerator. Multiply
by y to get
. Multiply
by x to get
. Then, combine numerators to get
. Then, put the numerator over the denominator to get your answer:
.
First, find the common denominator, which is . Then, make sure to offset each numerator. Multiply
by y to get
. Multiply
by x to get
. Then, combine numerators to get
. Then, put the numerator over the denominator to get your answer:
.
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Subtract the expressions: 
Subtract the expressions:
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Make a common denominator:


Combine and subtract numerators:


Make a common denominator:
Combine and subtract numerators:
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To start this problem, you must first identify the common denominator, which in this case is teh two denominators multiplied together:
. Next, offset the numerators with the newly changed denominators:
. Then, add numerators to get:
. Put the numerator over your denominator and check to make sure it can't be simplified anymore (it can't). Your answer is:
.
To start this problem, you must first identify the common denominator, which in this case is teh two denominators multiplied together: . Next, offset the numerators with the newly changed denominators:
. Then, add numerators to get:
. Put the numerator over your denominator and check to make sure it can't be simplified anymore (it can't). Your answer is:
.
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To combine these rational expressions, first find the common denominator. In this case, it is
. Then, offset the second equation so that you get the correct denominator:
. Then, combine the numerators:
. Put your numerator over the denominator for your answer:
.
To combine these rational expressions, first find the common denominator. In this case, it is . Then, offset the second equation so that you get the correct denominator:
. Then, combine the numerators:
. Put your numerator over the denominator for your answer:
.
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Simplify: 
Simplify:
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First find the lowest common denominator. In this case, it will be x(x+2).
Multiply each fraction to get the common denominator then solve:



First find the lowest common denominator. In this case, it will be x(x+2).
Multiply each fraction to get the common denominator then solve:
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