SOLUTION: Can you please help me solve the problem? It's solving radical equations.
2x + square root (x+1) =8
The only thing in the square root is x + 1. I wasn't sure what sign to use
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-> SOLUTION: Can you please help me solve the problem? It's solving radical equations.
2x + square root (x+1) =8
The only thing in the square root is x + 1. I wasn't sure what sign to use
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Question 205310: Can you please help me solve the problem? It's solving radical equations.
2x + square root (x+1) =8
The only thing in the square root is x + 1. I wasn't sure what sign to use on the keyboard for that.
I know the answer is 3, but I don't understand how to get it. I know you have to square both sides. Thank you. Answer by stanbon(75887) (Show Source):
You can put this solution on YOUR website! 2x + square root (x+1) =8
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Isolate the square root term:
sqrt(x+1) = 8-2x
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Square both sides to get:
x+1 = 64 -32x + 4x^2
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Modify:
4x^2 -33x +63 = 0
(x-3)(4x-21) = 0
x = 3 or x = 21/4
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Checking those "answers":
Try x = 3 in 2x + sqrt (x+1) =8 and you get: 6 + sqrt(4) = 8
6 + 2 = 8
Good answer.
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Try x = 21/4 in 2x + sqrt(x+1) =8 and you get
(21/2) + sqrt(25/4) = 8
(21/2) + 5/2 = 8
13 = 8
That is false so x=21/4 is an extraneous answer.
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Cheers,
Stan H.
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