diff --git a/src/3_drude_model_solutions.md b/src/3_drude_model_solutions.md
index 6b9920123c49770ed80f3a94435b8b1b2a28ae5e..8238cd7965693f348691c18124273ee88eb19c0c 100644
--- a/src/3_drude_model_solutions.md
+++ b/src/3_drude_model_solutions.md
@@ -74,7 +74,7 @@ $$
 $$
 
 $$
-\frac{dv_y}{dt} = \frac{eBv_x}{m} + \frac{eE}{m}
+\frac{dv_y}{dt} = \frac{eBv_x}{m} - \frac{eE}{m}
 $$
 
 Repeat steps followed in 2. to compute x(t) and y(t) after which the particle motion is given by,