Clear fractions by multiplying every term, including two fractions on one side and the unknown on the bottom.
What you will learn
- Solve equations with one fraction
- Clear several fractions with a common denominator
- Solve when x is in the denominator
Multiply every term
Multiply both sides (every term) by the denominator to clear it.
- (2x + 1)/3 = 5
- multiply by 3: 2x + 1 = 15
- 2x = 14, so x = 7
A number times x over a denominator works the same way: 3x/4 + 1 = 7 gives 3x/4 = 6, then 3x = 24, so x = 8. If the right side is 0, as in (4x − 8)/5 = 0, then 4x − 8 = 0 and x = 2.
With two denominators, multiply by a common multiple: x/2 + x/3 = 10 becomes 3x + 2x = 60, so x = 12.
The rest of this lesson and its 7 practice questions are locked.
In this lesson
- Multiply every term
- A fraction on each side, or a minus between them
7 practice questions, marked as you go; about 25 minutes in all.
In this unit: Linear equations and inequalities
Solve linear equations of every shape, including brackets and fractions, form equations from problems, and solve and show inequalities.