MHB Solve sqrt (x+ a) = x −7 when a=-1

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The equation sqrt(x - 1) = x - 7 is analyzed with a = -1. Substituting potential solutions, x = 5 yields an incorrect result, as 2 does not equal -2. Similarly, testing x = 10 also fails to satisfy the equation. The discussion concludes that there is no valid solution for the equation when a = -1. Therefore, the solution set is determined to be no solution.
rebo1984
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Hi,

If a = -1, what is the solution set of the equation sqrt (x+ a) = x −7

{5}
{10}
{5, 10}
No solution(5,10) correct?

Thanks
 
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rebo1984 said:
Hi,

If a = -1, what is the solution set of the equation sqrt (x+ a) = x −7

{5}
{10}
{5, 10}
No solution(5,10) correct?

Thanks

What do you get when you substitute each potential solution into the original equation?
 
MarkFL said:
What do you get when you substitute each potential solution into the original equation?

It works out.
 
rebo1984 said:
It works out.

Let's try \(x=5\):

$$\sqrt{5-1}=5-7$$

$$2=-2$$

Is this true?
 
rebo1984 said:
It works out.
What "works out"? Which answer did you get?
 
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