When two resistors are connected in series, the equivalent resistance \(R_{\text{eq}}\) is the sum of individual resistances. Using the formula \(R = \frac{V^2}{P}\) for each resistor, the equivalent resistance becomes:
\[
R_{\text{eq}} = \frac{V_1^2}{P_1} + \frac{V_2^2}{P_2}
\]