I was playing with web3.eth.accounts.create([entropy]) function and I can easily create a new Ethereum account and get the address and the private key.
I created a simple address/private key pair and accessed to My Ether Wallet to try accessing to the address wallet. I can access with no problems, but I noticed that I was only asked to introduce the private key, no need to access the address.
How can it figure out my Ethereum address only based on the private key? Sorry if the answer is very basic but I cannot find a good explanation to that. I know that Ethereum wallet is based on the public/private key (assymetric) cryptography, but I thought that you need to provide both to login.