Other possible answers:
1+1+16+25
1+1+9+16+16
... the pattern you see though is that there is no combination of square numbers greater than 1 that adds up to 43.
43 x 43 x 43
43 is a prime number. So, 43 can only be produced as a product of 1 times 43.
75 - 32
21 and 22
They are: 29*43 = 1247
(2 + 9) x 4 - 1 = 43
86*1 43*2
2 and 43 (they are the only ones)
43 = XLIII
1 and 43
-43
50