Question

3^x-5. 3^2x =  81. Tìm x 

Answer 1

Ta co : 

3^x-5 .3^2x=81

3^x-5.3^2x=3⁴

x-5.2x  = 4

Tu tinh tiep 

Answer 2

   3^x-5.3^2x=81

=>3^x-5+2x=3⁴

=>x-5+2x=4

=>x+2x-5=4

=>3x=4+5

=>3x=9

=>x=3

Answer 3

X= 3 

TICK MÌNH NHÉ CHU MINH NGỌC

Answer 4

   3^x-5.3^2x=81

=>3^x-5+2x=3⁴

=>x-5+2x=4

=>x+2x-5=4

=>3x=4+5

=>3x=9

=>x=3

DỄ VẬY MÀ KO BIK LÀM