npub14lmh8azph6ll8fsf6xx4rc8882ulaaagsautxufnv0p7w3qedrhsa75crk (npub14lm…5crk)
One of these problems, you could easily solve with a computer program and brute force, but requires is thinking if you want to do it properly.
BTW: Why didn't you write (-3y + 7y) as 4y?