Let A = Alabama appearances, T for Tennessee and X for Texas
A+T+X=141
A=T+8
T+X=37+A
Substitute to eliminate A
T+ 8 + T + X = 141 => 2T + X = 133
T + X = 37 + T + 8 => X = 45
Then 2T + 45 = 133 => T = 44
and then A = 52
Please go back and plug these answers into the original equation to be sure they are correct.