SOLUTION: The sqare of the difference between a number and 7 is 9. find the number(s)

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Question 1035827: The sqare of the difference between a number and 7 is 9. find the number(s)
Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
+%28+n+-+7+%29%5E2+=+9+
Take the square root of both sides
+n+-+7+=+3+
Add +7+ to both sides
+n+=+10+
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Now take the negative square root of +9+
+n+-+7+=+-3+
+n+=+4+
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The numbers are 4 and 10
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check answers:
+%28+n+-+7+%29%5E2+=+9+
+%28+10+-+7+%29%5E2+=+9+
+3%5E2+=+9+
+9+=+9+
OK
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+%28+n+-+7+%29%5E2+=+9+
+%28+4+-+7+%29%5E2+=+9+
+%28-3%29%5E2+=+9+
+9+=+9+
OK