\(5^2.7^3.11^2.x+5^3.7^2.11=0\)

=>\(5^2.7^2.11.\left(77x+5\right)=0\)

=>\(77x+5=0\)

=>77x=-5

=>\(x=-\dfrac{5}{77}\)

\(5^2.7^3.11^2.x+5^3.7^2.11=0\)

\(5^2.7^2.11.\left(77x+5\right)=0\)

\(77x+5=0\)

\(77x=-5\)

\(x=\dfrac{-5}{77}\)

\(5^2.7^3.11^2.x+5^3.7^2.11=0\)

\(\Leftrightarrow5^2.7^2.11\left(7.11.x+5\right)=0\)

\(\Leftrightarrow77x+5=0\)

\(\Leftrightarrow77x=-5\)

\(\Leftrightarrow x=-\frac{5}{77}\)

Ta có: 5².7³.11².x - 5².7².11⁴ = 0

=> 5².7².11²(7x - 11²) = 0

=> 7x - 121 = 0

=> 7x = 121

=> x = 121 : 7

=> x = 121/7

<=>5^2.7^3x+5^3.7^2.11=125(7x+55)

=>1225(7x+55)=0

=>8575x+67375=0

=>8575x=-67375

=>1225.7x=1225.(-55)

=>7x=-55

=>x=\(\frac{-55}{7}\)

x=\(\frac{-55}{7}\)

a,2.7^x+1-3.7^x=77

=>2.7^x.7¹-3.7^x=77

=>7^X.(2.7-3)=77

=>7^x.11=77

=>7^x=7

=>7^x=7¹

=>x=1

\(\dfrac{5}{6}-\dfrac{1}{2}\left(x-\dfrac{1}{3}\right)-\dfrac{2}{5}x=0\Rightarrow\dfrac{1}{2}\left(x-\dfrac{1}{3}\right)-\dfrac{2}{5}x=\dfrac{5}{6}\)

\(\Rightarrow\dfrac{1}{2}x-\dfrac{1}{6}-\dfrac{2}{5}x=\dfrac{5}{6}\Rightarrow\dfrac{1}{2}x-\dfrac{2}{5}x=\dfrac{5}{6}+\dfrac{1}{6}=1\)

\(\Rightarrow x\left(\dfrac{1}{2}-\dfrac{2}{5}\right)=1\Rightarrow\dfrac{1}{10}x=1\Rightarrow x=1:\dfrac{1}{10}=10\)

Vậy x = 10