Respuesta :

Answer:

21

Step-by-step explanation:


Answer:

(a)

[tex](x+1)^2=32[/tex]

(b)

[tex](x+1-\sqrt{32})(x+1+\sqrt{32}) =0[/tex]

Step-by-step explanation:

We are given

[tex]x^2+2x=31[/tex]

Since, we have to complete square

so, we can use formula

[tex]a^2+2ab+b^2=(a+b)^2[/tex]

[tex]x^2+2\times x\times 1=31[/tex]

so, we can add both sides by 1^2

[tex]x^2+2\times x\times 1+1^2=31+1^2[/tex]

now, we can use formula

and we get

[tex](x+1)^2=32[/tex]

so, equation after completing square is

[tex](x+1)^2=32[/tex]

now, we can solve for x

we can move all terms on left side

[tex](x+1)^2-32=0[/tex]

[tex](x+1)^2-(\sqrt{32})^2 =0[/tex]

now, we can factor it

[tex](x+1-\sqrt{32})(x+1+\sqrt{32}) =0[/tex]