Can I deploy my web app on Heroku and my wordpress blog on Google?

let's assume I own xyz.com. Now I've written an app in Node.js. I want to deploy that nodejs app on xyz.com and let's assume I want to have a wordpress blog(which is written in php) on the subdomain blog.xyz.com. Here comes the problem:The domain and the blog is hosted on GoDaddy and the app on Heroku.

Can I pull this off? Thank you.

Yes you can do it no problem. In your GoDaddy domain settings, the A record for xyz.com points to your heroku app. And the A record for blog.xyz.com points to the GoDaddy hosting. And when you setup wordpress, make sure that the home_url and site_url are set to blog.xyz.com.