Răspuns :
(1/3 )^ (2x+10) = 81
(1/3)^ (2x +10) = 3^4
(1/3)^(2x +10) = (1/3)^-4
2x + 10 = - 4
2x = - 4 - 10
2x = - 14
x = - 14 : 2
x = - 7
(1/3 )^ (2x+10) = 81
(1/3)^ (2x +10) = 3^4
(1/3)^(2x +10) = (1/3)^-4
2x + 10 = - 4
2x = - 4 - 10
2x = - 14
x = - 14 : 2
x = - 7