Answer :

Candyzz100

raAnswer:

x = 5

Step-by-step explanation:

Original equation = [tex]\sqrt{2x+6}[/tex] - [tex]\sqrt{x+4}[/tex] = 1

Remove square roots

[tex]x^{2}[/tex] + 2x +1 = 4x +16

Subtract 16 from both sides

[tex]x^{2}[/tex]+ 2x +1 = 4x +16

           -16       -16

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

[tex]x^{2}[/tex]  + 2x- 15= 4x

Subtract 4x from both sides

[tex]x^{2}[/tex] + 2x - 15 - 4x= 4x - 4x

= [tex]x^{2}[/tex] - 2x - 15 = 0

THIS EQUATION HAS 2 rational roots. {x1,x2} = {5,-3}

CHECK THAT THE FIRST SOLUTION IS CORRECT (5)

    Original equation, root isolated, after tidy up

  [tex]\sqrt{2x+6}[/tex] = [tex]\sqrt{x+4}[/tex]

     Plug in 5 for  x

[tex]\sqrt{2\cdot (5)+6}[/tex] = [tex]\sqrt{(5)+4+1}[/tex]

        Simplify

      [tex]\sqrt16}[/tex] = 4

  Solution checks !!

     Solution is: x = 5

CHECK THAT THE SECOND SOLUTION IS CORRECT (-3)

 Original equation, root isolated, after tidy up

  [tex]\sqrt{2x+6}[/tex] = [tex]\sqrt{x+4}[/tex]

   Plug in  -3 for  x

  [tex]\sqrt{2\cdot (-3) +6}[/tex] = [tex]\sqrt{(-3)+4+1}[/tex]

       Simplify

[tex]\sqrt{0}[/tex] = 2

 Solution does not check

          0 ≠ 2

   So, the answer is x = 5

Hope this helps!

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