$\sqrt{2} \times \sqrt{64+16}$

Correct answer marked below

40

4 \sqrt{10}

Correct

8 \sqrt{2} + 4

12 \sqrt{2}

32 \sqrt{2}

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Comments

MmesomaJun 1

wait why isn't it just 16? do we have to simplify the root after adding inside?

NicolásJun 6

yeah you have to add first then break up the root, you can't split it the other way around

AviMay 4

Got B pretty quick. add inside, factor out a perfect square, multiply the leftover 2's. nice warmup.

TanishaSep 1

C tripped me up for a sec cause it looked like a distribute thing, but you can't split a root over addition like that.

What this question tests

Your handling of square and higher roots, including simplifying radicals.

Forgetting the ± when taking a square root to solve an equation, or assuming √(a²) = a.