340. \( 2 x^{2}-5 x+x^{2}-x \)

Let's simplify the expression \( 2x^{2} - 5x + x^{2} - x \). We start by combining like terms: 1. Combine the \( x^{2} \) terms: \( 2x^{2} + x^{2} = 3x^{2} \). 2. Combine the \( x \) terms: \( -5x - x = -6x \). So, the expression simplifies to: \[ 3x^{2} - 6x \] Now, if you’re feeling adventurous, you can factor it out: \[ 3x(x - 2) \] And there you have it - the expression is simplified and factored!