Given the equation [tex]\sqrt{2x+1}=3[/tex], solve for x and identify if it is an extraneous solution.

A. [tex]x=4[/tex], solution is extraneous
B. [tex]x=4[/tex], solution is not extraneous
C. [tex]x=5[/tex], solution is extraneous
D. [tex]x=5[/tex], solution is not extraneous



Answer :

Let's solve the given equation [tex]\(\sqrt{2x + 1} = 3\)[/tex] step by step.

1. First, we need to eliminate the square root. We can do this by squaring both sides of the equation:
[tex]\[ (\sqrt{2x + 1})^2 = 3^2 \][/tex]

2. Simplifying both sides, we get:
[tex]\[ 2x + 1 = 9 \][/tex]

3. Next, solve for [tex]\(x\)[/tex]. To do this, isolate the [tex]\(x\)[/tex] term:
[tex]\[ 2x + 1 - 1 = 9 - 1 \][/tex]
[tex]\[ 2x = 8 \][/tex]

4. Divide both sides by 2 to solve for [tex]\(x\)[/tex]:
[tex]\[ x = \frac{8}{2} \][/tex]
[tex]\[ x = 4 \][/tex]

So, we have found that [tex]\(x = 4\)[/tex].

5. Now, we need to check if this solution is extraneous. An extraneous solution is one that does not satisfy the original equation.

Substitute [tex]\(x = 4\)[/tex] back into the original equation [tex]\(\sqrt{2x + 1} = 3\)[/tex]:
[tex]\[ \sqrt{2(4) + 1} = \sqrt{8 + 1} = \sqrt{9} \][/tex]

6. Simplifying the right hand side:
[tex]\[ \sqrt{9} = 3 \][/tex]

Since both sides of the original equation are equal when [tex]\(x = 4\)[/tex], the solution is valid.

Therefore, the solution is:
[tex]\(x = 4\)[/tex], solution is not extraneous