Op-amp subtractor

@Wawa,
Dumb question;
I recognize the Gain of 11 non-inverting amplifier but what is the purpose of the 4k pullup on the -V pin ?
That should yield a voltage divider output of 1.0 V. Is that how you offset the circuit to 0.9 to 1.4V ?
(by biasing the virtual ground)

Robert