diff --git a/docs/documentation/equations.md b/docs/documentation/equations.md
index 1f7470768..b8fb3b956 100644
--- a/docs/documentation/equations.md
+++ b/docs/documentation/equations.md
@@ -419,7 +419,7 @@ Additional geometric source terms appear with \f$1/r\f$ factors in the continuit
 
 **Modified mixture pressure:**
 
-\f[p = (1 - \alpha)\,p_l + \alpha\left(\frac{R^3\,p_{bw}}{\bar{R}^3} - \frac{\rho\,R^3\,\dot{R}^2}{\bar{R}^3}\right)\f]
+\f[p = (1 - \alpha)\,p_l + \alpha\left(\frac{R^3\,p_{bw}}{\bar{R}^3} + \frac{\rho\,R^3\,\dot{R}^2}{\bar{R}^3}\right)\f]
 
 **Modified stiffened gas for the liquid phase:**