Radical Expressions
11-8Adding and Subtracting Radicals
Overview
Only like radicals (same radicand) can be combined: a√c + b√c = (a + b)√c.
Key ideas
- Simplify each radical first.
- Combine coefficients of like radicals.
- Unlike radicals stay separate.
Worked examples
Example 1
Problem. Simplify 2√3 + 5√3.
Solution. 7√3
Example 2
Problem. Simplify √8 + √2.
Solution. 2√2 + √2 = 3√2
Practice
Try each one. Click Show answer when ready.
- 1.
4√5 − 2√5
- 2.
√18 + √2
- 3.
√27 − √12
Challenge problems
A little tougher — great for test prep. Click Show answer when ready.
- 1.
Simplify 3√8 + 2√18 − √50.
- 2.
Simplify 5√12 − 3√27 + √48.