Respuesta :

the answer is the second choice. u^2+7u-8=0 where u=3x=2

we have

[tex](3x+2)^{2}+7(3x+2)-8=0[/tex] --------> equation [tex]1[/tex]

let's change of variable

[tex]u=(3x+2)[/tex] --------> equation [tex]2[/tex]

substitute in the equation [tex]2[/tex] in equation [tex]1[/tex]

[tex](u)^{2}+7(u)-8=0[/tex]

therefore

the answer is

[tex](u)^{2}+7(u)-8=0[/tex]