Can someone please explain this problem to me? It's confusing.
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Answer:
The answer is ±8
Step-by-step explanation
Remember that the answer to a square root is the number that multiplied by himself is equal to the number given----> in this case (64=8·8)
When you have a square root(sqrt) there are two posibble solutions:
A positive one and a negative one
in this case 8·8=64 and (-8)·(-8)=64 so both answers are posible
+√64=8
-√64=-8
±√64=±8