I’ve been reading about ECDSA at over here.
Step 11 says it
You only need the value of “x” (20 bytes) to sign, this value will be called “R”
Does this mean that R is the x coordinate of the public key. But I don’t see that happening in the initial transactions.
For a pizza transaction, scriptSig looks like this
The first is the signature, and the second is the public key. I don’t see any relationship between these two items.