3^(4x+5)-2^(4x+7)-3^(4x+3)-2^(4x+4)=0
3^(4x+5)-3^(4x+3)=2^(4x+7)+2^(4x+4)
(3^(4x+3))*(3²-3⁰)=(2^(4x+4))*(2³+2⁰)
(3^(4x+3))*(9-1)=(2^(4x+4))*(8+1)
(3^(4x+3))*8=(2^(4x+4))*9 |: 72
(3^(4x+3))/9=(2^(4x+4))/8
3^(4x+3-2)=2^(4x+4-3)
3^(4x+1)=2^(4x+1)
a^m=b^m, ⇒m=0
4x+1=0, 4x=-1
x=-0,25