If it is open and shows on your report, then activate it. It will show a zero balance on a line of credit, which will also boost your scores. It won't change your debt to income ratio though. Unless you use it, which then it will make your debt higher. I can refer you to a local lender who can look at your DTI, your credit, and tell you if its better to pay down the debt and get a lender credit with a slightly higher interest rate, or to leave it alone.
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