V_A = \dfrac{R_B}{R_A + R_B} V_2 = V_B
V_0=V_1-\dfrac{V_1 - V_B}{R_1}(R_1 + R_2)
\displaystyle=-\dfrac{R_2}{R_1} V_1+\left(1 + \dfrac{R_2}{R_1}\right)\dfrac{R_B}{R_A + R_B} V_2
\displaystyle R_2 = 11\text{k}\Omega,\;R_A = 23\text{k}\Omega\;\Rightarrow\;R_A - R_2 = 12\text{k}\Omega