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Which statement describes if there is an extraneous solution to the equation √x-3 = x-5? A. there are no solutions to the equation, B. the extraneous solution is x = 7, C. the valid solutions are x = 7 and x = 4, or D. the extraneous solution is x = 4

User Jovobe
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2 Answers

4 votes

Answer:

x=4

Explanation:

did this on iready hope it helps

User TonioElGringo
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Remember that an extraneous solution of an equation, is the solution that emerges from solving the equation but is not a valid solution.

Lets solve our equation to find out what is the extraneous solution:

√(x-3) =x-5

(√(x-3))^2 =(x-5)^2

x-3=x^2-10x+25

x^2-11x+28=0

(x-4)(x-7)=0

x-4=0 and
x-7=0

x=4 and
x=7

So, the solutions of our equation are

x=4 and
x=7. Lets replace each solution in our original equation to check if they are valid solutions:
- For
x=7

√(x-3) =x-5

√(7-3) =7-5

√(4) =2

2=2
We can conclude that 7 is a valid solution of the equation.

- For
x=4

√(x-3) =x-5

√(4-3) =4-5

√(1) =1

1 \\eq 1
We can conclude that 4 is not a valid solution of the equation; therefore, 4 is a extraneous solution.

We can conclude that the correct answer is: D. the extraneous solution is x = 4
User JoseCarlosPB
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