ax+3x+4a+12

To simplify the expression \( ax + 3x + 4a + 12 \), we can combine like terms. In this case, we can group the terms involving \( x \) and the constant/term without \( x \):

1. Group the \( x \) terms:

   • \( ax + 3x = (a + 3)x \)

2. Combine the constant terms:

   • The constant term here is just \( 4a + 12 \).

Putting it all together, the simplified expression is: \[ (a + 3)x + 4a + 12 \]

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