(x-3) + (x-2) + (x-1) +...+10 + 11 =11, (x - 3) + (x - 2) + (x - 1) +...+ 10 + 11 = 11, (x - 3) + (x - 2) + (x - 1) + ... + 10 + 11 = 11, (x-3)+(x-2)+(x-1) +.....+10+11=11