Add $ \dfrac{3x-1}{2x+4} $ and $ \dfrac{2x-1}{x-1} $ to get $ \dfrac{ \color{purple}{ 7x^2+2x-3 } }{ 2x^2+2x-4 }$.

To add raitonal expressions, both fractions must have the same denominator.
We can create a common denominator by multiplying the first fraction by $ \color{blue}{ x-1 }$ and the second by $\color{blue}{ 2x+4 }$.

$$ \begin{aligned} \frac{3x-1}{2x+4} + \frac{2x-1}{x-1} & = \frac{ \left( 3x-1 \right) \cdot \color{blue}{ \left( x-1 \right) }}{ \left( 2x+4 \right) \cdot \color{blue}{ \left( x-1 \right) }} + \frac{ \left( 2x-1 \right) \cdot \color{blue}{ \left( 2x+4 \right) }}{ \left( x-1 \right) \cdot \color{blue}{ \left( 2x+4 \right) }} = \\[1ex] &=\frac{ \color{purple}{ 3x^2-3x-x+1 } }{ 2x^2-2x+4x-4 } + \frac{ \color{purple}{ 4x^2+8x-2x-4 } }{ 2x^2-2x+4x-4 } = \\[1ex] &=\frac{ \color{purple}{ 7x^2+2x-3 } }{ 2x^2+2x-4 } \end{aligned} $$