(3b-4c)^2 = (4a+3b)^2 = (3+2a)^2 = (9-8c)^2 =
1. (3b-4c)2 = 9b2-24bc+16c2
2. (4a+3b)2 = 16a2+24ab+9b2
3. (3+2a)2 = 9+12a+4a2
4. (9-8c)2 = 81-144c+64c2