SOLUTION: simplify sqrt (8) times sqrt (2) - 7

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Question 611036: simplify sqrt (8) times sqrt (2) - 7
Found 2 solutions by radh, ashipm01:
Answer by radh(108) About Me  (Show Source):
You can put this solution on YOUR website!
First of all, we'd combine the square roots under the radicals to have sqrt(8*2), simplified to sqrt(16). The square root of 16 is 4. We'd end up with 4-7, which equals -3. :)

Answer by ashipm01(26) About Me  (Show Source):
You can put this solution on YOUR website!
Restating your original problem just to make it easier to read:
+sqrt%288%29%2Asqrt%282%29+-+7+
That can be simplified by first prime factorizing 8, which results in the prime factors of 2 * 2 * 2. So now the problem can be rewritten by substituting the prime factors for 8:
+sqrt%282%2A2%2A2%29%2Asqrt%282%29+-+7+
You can split those all out separately:
+sqrt%282%29%2Asqrt%282%29%2Asqrt%282%29%2Asqrt%282%29+-+7+
Since sqrt%282%29%2Asqrt%282%29+=+2, the above problem can be simplified as:
+2%2A2+-+7
Which can then be further simplified as:
-3