From the point of view of the borrower, the haircut is added to the amount you have to borrow, as I did. Though, properly, it's not 1+x but 1/(1-x) as Jake pointed out.

From the point of view of the lender, obviously, the haircut is a discount on the value of the collateral.

I want to borrow 100, I need to pledge 105 worth of assets.

I am receiving an asset worth 100 as collateral, I will offer a loan of 95.

Economics is politics by other means