The expression 5(x+3) - 9x + 4 simplifies to -4x + 19, which is achieved by distributing the multiplication, combining like terms, and adding constant values.
The question involves simplifying a mathematical expression, which falls under the area of basic algebra. To simplify the expression 5(x+3) - 9x + 4, we first need to distribute the 5 across the terms inside the parentheses.
5(x + 3) = 5x + 15
Next, we combine like terms by subtracting 9x from 5x.
5x - 9x = -4x
Finally, we add the constant terms.
15 + 4 = 19
So, when we combine all our work, the expression simplifies to -4x + 19, which is Option C.
To ensure the answer is reasonable, we can review the steps to confirm that terms have been correctly eliminated wherever possible. The given expression is simplified by distributing, combining like terms, and then adding constants. No further simplifications can be made, confirming that our answer is indeed reasonable.