diff --git a/src/MOI_wrapper.jl b/src/MOI_wrapper.jl
index 3ac4f57..0c187bf 100644
--- a/src/MOI_wrapper.jl
+++ b/src/MOI_wrapper.jl
@@ -231,7 +231,9 @@ function _add!(
         end
         vectorized = set.vectors[row]::TriangleVectorization
         matrix = vectorized.matrix
-        @assert isone(coef) # TODO multiply scaling
+        if !isone(coef)
+            matrix = mul_scaling(matrix, coef)
+        end
         _add!(A, matrix)
     end
 end
diff --git a/src/factorization.jl b/src/factorization.jl
index a0884b0..27a4a52 100644
--- a/src/factorization.jl
+++ b/src/factorization.jl
@@ -83,6 +83,8 @@ function Factorization(factor::AbstractVector{T}, scaling::T) where {T}
     return Factorization(factor, fill(scaling, tuple()))
 end
 
+mul_scaling(m::Factorization, coef) = Factorization(m.factor, m.scaling * coef)
+
 left_factor(m::Factorization) = m.factor
 right_factor(m::Factorization) = m.factor