Решить уравнение 5^(4x)+3*5^(4x-2)=140

[latex]5^{4x}+3*5^{4x-2}=140\\5^{4x-2}(5^{4x-4x+2}+3)=140\\5^{4x-2}(5^2+3)=140\\5^{4x-2}*(25+3)=140\\5^{4x-2}*28=140\\5^{4x-2}=140:28\\5^{4x-2}=5^1\\4x-2=1\\4x=2+1\\4x=3\\x=3/4\\x=0,75[/latex]