AH odds

Hello,

I was wondering if it's possible to calculate "fair odds" on -0,75 AH if you know the line for -0,5 and -1.
It looks much easier for -0,25 since you don't have "half win scenario":

a-odds on 0:0 AH
b-odds on -0,5 AH
x odds on -0,25 AH

If you win (both handicaps covered) you get the same as if you had bet 0,5 of your stake on 0:0 AH and 0,5 on -0,5 AH:

a*0,5 0,5*b-1=x*1-1
x=(a b)/2

If you "half lose" your result is always -0,5 (independent on the odds).
If you lose, you lose everything.

The first part looks the same for -0,75 but in the "half win" scenario things are getting a little bit more complex:
In case my team wins by one goal, I get 0,5*"odds on -0,5 AH" minus 0,5 (half refund-whole stake). It's exactly the same when I take -0,75 AH except for the fact that this time I put odds on -0,75 in the equation so all I learn is that odds on -0,5 and -0,75 should be equal, which is as obvious bullshit as you get.
Could anybody help me with that problem, please?

Lucas

Answering own questions may be a syndrome of some kind of mental disorder but, believe it or not, it was the very first thing I thougt of after waking up in the morning.
If one team is -0,75, their opponents are +0,75, which is a potential "half lose" sittuation. So it's easy to count the odds for them and than convert them for the "-0,75 team".
Sorry for the mess:o .

Lucas