Given that 131 base n _ 143 equal to 44 base n find number base n

Answer 1

I do not understand n _143

131 base n = n^2 + 3 n + 1
143 base n = n^2 + 4 n + 3
44 base n = 4 n + 4

Answer 2

for some reason people like to use _ instead of -

but regardless of the base, 131-143 will be negative, so it cannot be 44.