Simplify
$- 2 \sqrt{5} + 2 \sqrt{20}$

Select the correct choice below and fill in any answer boxes in your choice.
A. $- 2 \sqrt{5} + 2 \sqrt{20} = ◻$
(Simplify your answer. Type an exact answer, using radicals as needed.)
B. The expression cannot be simplified.

Answer

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Answer

We can combine like terms to get the final answer: $- 2 \sqrt{5} + 4 \sqrt{5} = 2 \sqrt{5}$

Steps

Step 1 ：The given expression is $- 2 \sqrt{5} + 2 \sqrt{20}$ .

Step 2 ：We can simplify the square root of 20 to 2 times the square root of 5, so the expression becomes $- 2 \sqrt{5} + 2 * (2 \sqrt{5})$ .

Step 3 ：This simplifies to $- 2 \sqrt{5} + 4 \sqrt{5}$ .

Step 4 ：We can combine like terms to get the final answer: $- 2 \sqrt{5} + 4 \sqrt{5} = 2 \sqrt{5}$