Respuesta :

2(x+7) + x=20
(2)(x) + (2)(7) + x=20  Distribute 
2x+14 + x =20
(2x+x) + (14) =20  Combine Like Terms 
3x+14=20 
    - 14  -14             Subtract 14 from both sides 
3x = 6 
3x/3 6/3                  Divide Both Sides by 3 
 
x = 2 


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