SOLUTION: Solve the equation: square root x + 7 = 4

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Question 63640: Solve the equation:
square root x + 7 = 4
Answer by Earlsdon(6294) About Me  (Show Source):
You can put this solution on YOUR website!
Try using parentheses to show your problem more clearly:
Is it
1) sqrt%28x%29+%2B+7+=+4? If this, then write: sqrt(x) + 7 = 4 or is it:
2) sqrt%28x%2B7%29+=+4? If this, then write: sqrt(x+7) = 4
If it's 1):
sqrt%28x%29+%2B+7+=+4 Subtract 7 from both sides.
sqrt%28x%29+=+-3 Square both sides.
x+=+9
Check:
sqrt%289%29+%2B+7+=+4 Only the negative 3 (-3) is a valid solution.
-3+%2B+7+=+4
4+=+4
If it's 2):
sqrt%28x%2B7%29+=+4 square both sides.
x%2B7+=+16 Subtract 7 from both sides.
x+=+9
Check:
sqrt%289%2B7%29+=+4
sqrt%2816%29+=+4 4+=+4 Only the positive 4 (+4) is a valid solution.
4+=+4