AWS: Can we cosider having "multiple EC2 instances and RDS " for a single product as horizontal scaling?

Question

What I read in stack overflow and other blogs-

Difference between scaling horizontally and vertically for databases

http://ht.ly/cAhY6

https://hackernoon.com/database-scaling-horizontal-and-vertical-scaling-85edd2fd9944

Can relational database scale horizontally

Concept: Multi-tenant web app(CRM)

After summarizing all blogs mentioned above I got confused. I have following scenario

• Having multiple EC2 instances and RDS instances for a single product - Here we planned one EC2 instance will have one RDS and failover plans. Let's come with figure- 25 tenants requests will be handled in one EC2 instance and data will be managed in corresponding RDS. Another EC2 instance and RDS will be managed for another set of 25 tenants. Each EC2 instance will have the same code base.

Can we say - it's horizontal scaling?