To simplify this expression, we need to combine the like terms, which are the terms with the same variable (in this case, x).
Given expression: 3x + 2x - 5x
Step 1: Combine the like terms by adding the coefficients.
3x + 2x - 5x
= (3 + 2 - 5)x
= 0x
Step 2: Simplify the expression.
0x = 0
Therefore, the simplified expression is 0.