Question

Algebra: Rational & Irrational Numbers Unit test:
What must be true in order to combine radicals using addition or subtraction? Explain why it cannot always be immediately determined whether radicals can be combined with addition or subtraction. In 1 sentence.

Answer 1

In order to combine radicals using addition or subtraction, the radicals must have the same index and the same radicand (the number under the radical); however, it cannot always be immediately determined whether radicals can be combined because even if they share the same index, they may differ in their radicands, making them fundamentally different expressions.