Adding and Subtracting Rational Expressions Math Example 3

Follow the full solution, then compare it with the other examples linked below.

Example 3

easy
Add 3x+5x\frac{3}{x} + \frac{5}{x}.

Solution

  1. 1
    Same denominator: 3+5x=8x\frac{3 + 5}{x} = \frac{8}{x}.
  2. 2
    Check: At x=2x = 2: 32+52=4\frac{3}{2} + \frac{5}{2} = 4 and 82=4\frac{8}{2} = 4 ✓

Answer

8x\frac{8}{x}
When rational expressions share the same denominator, simply add (or subtract) the numerators and keep the common denominator.

About Adding and Subtracting Rational Expressions

Adding or subtracting rational expressions by finding a least common denominator (LCD), rewriting each fraction with the LCD, then combining the numerators over the common denominator.

Learn more about Adding and Subtracting Rational Expressions →

More Adding and Subtracting Rational Expressions Examples

Example 1 medium

Add [formula].

Example 2 hard

Subtract [formula].

Example 4 medium

Subtract [formula].

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