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Solve and explain if extraneous

Solve and explain if extraneous-example-1
User Cudos
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1 Answer

4 votes

Answer:

x = 5

Yes, this solution is extraneous.

Explanation:

Given equation:


√(3x+1)+8=4

Subtract 8 from both sides of the equation:


√(3x+1)+8-8=4-8


√(3x+1)=-4

Now, square both sides to eliminate the square root:


\left(√(3x+1)\right)^2=(-4)^2


3x+1=16

Subtract 1 from both sides of the equation:


3x+1-1=16-1


3x=15

Divide both sides by 3 to isolate x:


(3x)/(3)=(15)/(3)


x = 5

An extraneous solution is a solution that is produced by solving the problem, but is not a valid solution to the problem.

To check if the solution is extraneous, substitute x = 5 back into the original equation:


√(3(5)+1)+8\overset{?}=4


√(16)+8\overset{?}=4


4+8\overset{?}=4


12 \\eq4

Therefore, as the left side is not equal to the right side, the solution x = 5 is extraneous, and the equation has no solution.

User Adrpino
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7.9k points