SOLUTION: √(x² + 21) - 2 = x + 1

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Question 1136411: √(x² + 21) - 2 = x + 1
Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
+sqrt%28+x%5E2+%2B+21+%29+-+2+=+x+%2B+1+
+sqrt%28+x%5E2+%2B+21+%29+=+x+%2B+3+
Square both sides
+x%5E2+%2B+21.+=+x%5E2+%2B+6x+%2B+9+
+21+=+6x+%2B+9+
+6x+=+12+
+x+=+2+
--------------------
check:
+sqrt%28+2%5E2+%2B+21+%29+-+2+=+2+%2B+1+
+sqrt%28+25+%29+-+2+=+3+
+sqrt%28+25+%29+=+5+
OK