hannahdumb
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Solve the following system by the substitution method.
y ^2 = x ^2 - 9
- 2 y = x- 3
Select the correct choice below​ and, if​ necessary, fill in the answer box to complete your choice.

Respuesta :

snairrami18pban3c
From the 2nd equation we get :
[tex]x=3-2y[/tex]
Then we plug in the first equation :
[tex]y^2=(3-2y)^2-9[/tex]

so :
[tex]y^2=9-12y+4y^2-9[/tex]

we find this equation :

[tex]4y^2-12y=0[/tex]

By factorization we get :

[tex]4y(y-3)=0[/tex]

thus : [tex]y=0 \text{ or }y=3[/tex]

And we can get the values of x

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