ta có :

toàn đẹp trai nhất thế giới đây

ảo tưởng sức mạnh à bn ơi đúng là khùng mà

ok ddhwjjsssss

\(\frac{35}{4}=x\div\frac{8}{7}\)

\(x=\frac{35}{4}\times\frac{8}{7}\)

\(x=10\)

gn ugneg hg8ug

\(\frac{31}{2}\div0,4=x\div1\frac{1}{7}\)

\(\frac{31}{2}\div\frac{2}{5}=x\div\frac{8}{7}\)

\(\frac{155}{4}=x\div\frac{8}{7}\)

\(x=\frac{155}{4}\times\frac{8}{7}\)

\(x=\frac{310}{7}\)

\(5^x+5^{x+2}=650\)

\(\Rightarrow5^x+5^x\cdot5^2=650\) \(\Rightarrow5^x+5^x\cdot25=650\) \(\Rightarrow5^x\cdot\left(1+25\right)=650\)

\(\Rightarrow5^x\cdot26=650\) \(\Rightarrow5^x=25\) \(\Rightarrow x=2\)

\(A=\frac{3x+2}{x-3}\)

Để A là số nguyên thì \(3x+2⋮x-3\)

Vì: \(x-3⋮x-3\)

\(\Rightarrow\)\(3.\left(x-3\right)⋮x-3\)

\(\Rightarrow\)\(3x-3.3⋮x-3\)

\(\Rightarrow\)\(3x-9⋮x-3\)

Mà: \(3x+2⋮x-3\)

\(\Rightarrow\)\(\left(3x+2\right)-\left(3x-9\right)⋮x-3\)

\(\Rightarrow\)\(3x+2-3x+9⋮x-3\)

\(\Rightarrow\)\(\left(3x-3x\right)+\left(2+9\right)⋮x-3\)

\(\Rightarrow\)\(11⋮x-3\)

\(\Rightarrow\)\(x-3\inƯ\left(11\right)\)

\(\Rightarrow\)\(x-3\in\left\{-11;-1;1;11\right\}\)

\(\Rightarrow\)\(x\in\left\{-8;2;4;14\right\}\)

Vậy \(x\in\left\{-8;2;4;14\right\}\)

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