Respuesta :
ANSWER
x = 4, solution is not extraneous
EXPLANATION
The given equation is
[tex] \sqrt{2x + 1} = 3[/tex]
Square both sides of the equation.
[tex]2x + 1 = 9[/tex]
Group similar terms,
[tex]2x = 9 - 1[/tex]
[tex]2x = 8[/tex]
Divide both sides by 2.
[tex]x = 4[/tex]
Check
Put x=4 into the original equation.
[tex] \sqrt{2(4) + 1} = 3[/tex]
[tex] \sqrt{9} = 3[/tex]
[tex]3 = 3[/tex]
This statement is true.
Hence x=4 is not an extraneous solution.
Second choice is correct.
Answer:
The correct answer is:
x = 4, solution is not extraneous
Step-by-step explanation:
Extraneous solution--
It is the solution which is obtained from the equation i.e. by solving the equation but is not a valid solution to the equation.
True solution--
It is the solution which is obtained from the equation i.e. by solving the equation and is a valid solution to the equation.
Here we have the equation as:
[tex]\sqrt{2x+1}=3[/tex]
Now on squaring both the sides of the equation we have:
[tex](\sqrt{2x+1})^2=3^2\\\\2x+1=9\\\\2x=9-1\\\\2x=8\\\\x=\dfrac{8}{2}\\\\x=4[/tex]
and the solution is a valid solution since the square root function is defined for this value of x.
Hence, the solution is not a extraneous solution i.e. it is a true solution to the equation.