Answer:

x=3

Step-by-step explanation:

∴[tex]3x+3=12\\3x=12 -3\\3x=9\\x=3[/tex]

Verified answer

Answer:

[tex]x = 3[/tex]

Step-by-step explanation:

[tex]3(x + 1) = 12[/tex]

[tex]3x + 3 = 12[/tex]

[tex]3x + 3-3 = 12-3[/tex]

[tex]3x = 9[/tex]

[tex]So, x = 9/3\\= x = 3[/tex]

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