Question

Which of the following is an extraneous solution of the square root of -3x-2=x+2

Answer 1

Answer:

x=-6 is an extraneous solution

Step-by-step explanation:

we have

$\sqrt{-3x-2} =x+2$

squared both sides

$-3x-2=(x+2)^2$

$-3x-2=x^2+4x+4$

$x^2+7x+6=0$

solve the quadratic equation by graphing

The solution is x=-6 and x=-1

see the attached figure

Verify each solution

substitute the value of x in the original expression

For x=-6

$\sqrt{-3(-6)-2} =-6+2$

$\sqrt{16} =-4$

$4=-4$ ----> is not true

so

Is an extraneous solution

For x=-1

$\sqrt{-3(-1)-2} =-1+2$

$\sqrt{1} =1$

$1=1$ ----> is true

so

Is the solution