Simplifying algebraic fractions
Cancel common factors to simplify algebraic fractions; add and subtract algebraic fractions with numeric denominators; multiply and divide algebraic fractions.
Worked examples
Simplifying a single algebraic fraction
Straightforward
Problem
Simplify .
1
Write out the factors in the numerator and denominator.
2
Identify the highest common factor (HCF) of the numerator and denominator.
The HCF of 10 and 4 is 2, and appears in both. So the HCF is .
3
Divide both numerator and denominator by the HCF.
Answer
Adding algebraic fractions with different denominators
Moderate
Problem
Simplify .
1
Find the lowest common denominator (LCD) of 4 and 6.
Multiples of 4: 4, 8, 12, 16, Multiples of 6: 6, 12, 18, The LCD is 12.
2
Convert each fraction to an equivalent fraction with denominator 12.
3
Add the numerators, keeping the denominator the same.
Answer
Dividing algebraic fractions
Challenging
Problem
Simplify .
1
Rewrite the division as multiplication by the reciprocal of the second fraction.
2
Multiply numerators together and denominators together.
3
Simplify by cancelling common numeric and variable factors.
Answer
Practise
Q1·Straightforward
Which of the following is the simplified form of ?
Explanation
The HCF of 6 and 9 is 3. Dividing: .
Q2·Straightforward
Which of the following is the simplified form of ?
Explanation
. The HCF is . Cancelling: .
Q3·Straightforward
Which of the following is the simplified form of ?
Explanation
The HCF of 15 and 10 is 5. Dividing: .
Q4·Straightforward
Simplify . Enter the numeric value.
Explanation
. The terms cancel completely.
Q5·Moderate
Which of the following is the simplified form of ?
Explanation
The LCD of 3 and 4 is 12. Converting: and . Adding: .
Q6·Moderate
Which of the following is the simplified form of ?
Explanation
The LCD of 2 and 5 is 10. Converting: and . Adding: .
Q7·Moderate
Which of the following is the simplified form of ?
Explanation
The LCD of 4 and 8 is 8. Converting: . Subtracting: .
Q8·Moderate
Which of the following is the simplified form of ?
Explanation
The LCD of 3 and 6 is 6. Converting: . Subtracting: .
Q9·Challenging
Simplify . Enter the numeric value.
Explanation
. Both the terms and the factor of 4 cancel.
Q10·Challenging
Simplify . Enter the numeric value.
Explanation
.
Q11·Challenging
Which of the following is the simplified form of ?
Explanation
.
Q12·Challenging
Which of the following is the simplified form of ?
Explanation
.
Open Math
Simplifying algebraic fractions
Algebra · MA4-ALG-C-01
Name:
Date:
Q1Straightforward
Which of the following is the simplified form of ?
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- B.
- C.
- D.
Q2Straightforward
Which of the following is the simplified form of ?
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- B.
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- D.
Q3Straightforward
Which of the following is the simplified form of ?
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Q4Straightforward
Simplify . Enter the numeric value.
Q5Moderate
Which of the following is the simplified form of ?
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Q6Moderate
Which of the following is the simplified form of ?
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- D.
Q7Moderate
Which of the following is the simplified form of ?
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- B.
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- D.
Q8Moderate
Which of the following is the simplified form of ?
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- B.
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Q9Challenging
Simplify . Enter the numeric value.
Q10Challenging
Simplify . Enter the numeric value.
Q11Challenging
Which of the following is the simplified form of ?
- A.
- B.
- C.
- D.
Q12Challenging
Which of the following is the simplified form of ?
- A.
- B.
- C.
- D.
Worked solutions and answers at openmath.au/year-8/algebraic-techniques/simplifying-algebraic-fractions