Answer
$x=4$
Work Step by Step
Square both sides:
$(\sqrt{2x+1})^2=3^2
\\2x+1=9$
Subtract $1$ to both sides of the equation:
$2x+1-1=9-1
\\2x=8$
Divide $2$ to both sides of the equation:
$\frac{2x}{2} = \frac{8}{2}
\\x=4$
Check if the solution is valid:
$\sqrt{2\cdot4 + 1} = 3
\\\sqrt{9}=3
\\3=3$
True.
Thus, the solution is $x=4$.
