Equations with fractions
Solve equations involving fractions by multiplying both sides to clear the denominator.
Worked examples
Solving $\frac{x}{a} = b$
Straightforward
Problem
Solve for :
1
Identify the operation applied to .
has been divided by 7.
2
Multiply both sides by 7 to undo the division.
3
Simplify both sides.
4
Check by substituting back into the original equation.
✓
Answer
Solving $\frac{x + a}{b} = c$
Moderate
Problem
Solve for :
1
Multiply both sides by 3 to clear the fraction.
2
Simplify the left side.
3
Subtract 5 from both sides.
4
Check by substituting back.
✓
Answer
Solving equations with fractions on both sides
Challenging
Problem
Solve for :
1
Find the LCM of the two denominators.
The LCM of 4 and 7 is 28.
2
Multiply both sides by 28 to clear all fractions.
3
Simplify both sides.
4
Expand the right side.
5
Subtract from both sides.
6
Divide both sides by 3.
7
Check by substituting back.
and ✓
Answer
Practise
Q1·Straightforward
Solve for :
Explanation
Multiply both sides by 4: .
Q2·Straightforward
Solve for :
Explanation
Multiply both sides by 3: .
Q3·Straightforward
Solve for :
Explanation
Multiply both sides by 5: .
Q4·Straightforward
Solve for :
Explanation
Multiply both sides by 6: .
Q5·Moderate
Solve for :
Explanation
Multiply both sides by 4: . Subtract 3: .
Q6·Moderate
Solve for :
Explanation
Multiply both sides by 3: . Add 2: .
Q7·Moderate
Solve for :
Explanation
Multiply both sides by 5: . Subtract 1: . Divide by 2: .
Q8·Moderate
Solve for :
Explanation
Multiply both sides by 2: . Add 4: . Divide by 3: .
Q9·Challenging
Solve for :
Explanation
Multiply both sides by 10: . Expand: . Subtract : . Divide by 3: . Check: and . ✓
Q10·Challenging
Solve for :
Explanation
Multiply both sides by 21: . Expand: . Subtract : . Divide by 4: . Check: and . ✓
Q11·Challenging
Solve for :
Explanation
Multiply both sides by 6: . Expand: . Subtract : . Add 3: . Check: and . ✓
Q12·Challenging
Solve for :
Explanation
Multiply both sides by 6: . Expand: . Subtract : . Subtract 2: . Check: and . ✓