\(\text{a) }\frac{-4}{x-1}=\frac{x-1}{-9}\)
\(\Leftrightarrow\left(x-1\right).\left(x-1\right)=\left(-4\right).\left(-9\right)\)
\(\Leftrightarrow\left(x-1\right)^2=36\)
\(\Leftrightarrow x-1=\sqrt{36}\)
\(\Leftrightarrow x-1=6\)
\(\Leftrightarrow x=7\)
\(a,\frac{-4}{x-1}=\frac{x-1}{-9}\)
\(\Rightarrow(x-1)(x-1)=(-4)\cdot(-9)\)
\(\Rightarrow(x-1)^2=36\)
\(\Rightarrow(x-1)^2=6^2\)
\(\Rightarrow x-1=\pm6\)
\(\Rightarrow\hept{\begin{cases}x-1=6\\x-1=-6\end{cases}}\Rightarrow\hept{\begin{cases}x=7\\x=-5\end{cases}}\)
\(b,-1,75\cdot x+3\frac{3}{4}=-24\)
\(\Rightarrow-1,75\cdot x+3,75=-24\)
\(\Rightarrow-1,75\cdot x=-24-3,75\)
\(\Rightarrow-1,75\cdot x=-27,75\)
\(\Rightarrow x=-27,75:(-1,75)\)
Tính rồi tìm ra giá trị của x thôi :v
a) -4/x-1=x-1/-9
<=> (x-1).(x-1)=-4.-9
<=> (x-1)2 = 36
<=> (x-1)2 = (\(\pm\)62)
<=>\(\orbr{\begin{cases}x-1=6\\x-1=-6\end{cases}}\)
<=>\(\orbr{\begin{cases}x=6+1=7\\x=-6+1=5\end{cases}}\)
Vậy x \(\in\){7,5}
