Using multiple machine learning algorithms together
You can train multiple machine learning models with same data and based on accuracy and confusion_matrix response you can decide which one to use.

In theory, you don't need to combine/merge two different ML Models (you can enhance your pre-processing) 
but if you still want to use different models there are two approaches:


Ensemble (available with three categories - a) Bagging b) Boosting c) Stacking
Hybrid (This approach allow users to create own models (or use existing) and combine them for better prediction)


Note: You need to be careful with individual algorithm response before combining them together :)