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Can someone help me solve this??

Can someone help me solve this??-example-1
User Jumand
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2 Answers

5 votes
Refer to the attached image
Can someone help me solve this??-example-1
User Amarjit Dhillon
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3 votes

Answer: No solutions

=====================================================

Reason:

Subtract 5 from both sides


\sqrt{\text{x}}+5 = 0\\\\\sqrt{\text{x}}=-5\\\\

But recall that the range of the parent square root function is the set of nonnegative values. There's no way to have
\text{y} = \sqrt{\text{x}} produce a negative number.

Therefore, the equation
\sqrt{\text{x}}=-5 has no solutions.

----------------------------

Here's what happens if we squared both sides


\sqrt{\text{x}}=-5\\\\(\sqrt{\text{x}})^2=(-5)^2\\\\\text{x}=25\\\\

That's the potential answer, but we need to verify.


\sqrt{\text{x}}+5 = 0\\\\√(25)+5 = 0\\\\5+5 = 0\\\\10 = 0\\\\

We get a contradiction, which rules out x = 25 being a possible solution.

----------------------------

If you are a visual learner, then check out the graph below.

The curve
\text{y} = \sqrt{\text{x}}+5 never touches the x axis; this means there's no way for it to have a root and it verifies why
\sqrt{\text{x}}+5 = 0 has no solutions.

I used GeoGebra to make the graph, but Desmos is another useful option.

Can someone help me solve this??-example-1
User Tim Mironov
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8.2k points