Question

Tìm x:

a/ 2130-(x+130)+72=-64

b/135-|9-x|=35

c/10-|x+3|=-4-(-10)

Answer 1

a/ 2130-(x+130)+72=-64

\(2130-\left(x+130\right)=-64-72\)  \(2130-\left(x+130\right)=-136\)\(x+130=2130+136\)\(x+130=2266\)\(x=2266-130\)\(x=2136\)vậy x=2136

 

  

Answer 2

a/ 2130-(x+130)+72=-64

<=> -x-130+72+2130=-64

<=> x=2130+72-130+64=2136

b/135-|9-x|=35

<=> |9-x|=135-35=100

<=> \(\left[\begin{array}{nghiempt}9-x=100\\9-x=-100\end{array}\right.\)

<=>\(\left[\begin{array}{nghiempt}x=-91\\x=109\end{array}\right.\)

c/10-|x+3|=-4-(-10)

<=> |x+3|=10+4+(-10)

<=>|x+3|=4

<=>\(\left[\begin{array}{nghiempt}x+3=4\\x+3=-4\end{array}\right.\)

<=>\(\left[\begin{array}{nghiempt}x=1\\x=-7\end{array}\right.\)

Answer 3

c/10-|x+3|=-4-(-10)

\(10-\left|x+3\right|=6\)\(\left|x+3\right|=10-6\)\(\left|x+3\right|=4\)\(\Rightarrow\left[\begin{array}{nghiempt}x+3=4\\x+3=-4\end{array}\right.\Leftrightarrow\left[\begin{array}{nghiempt}x=4-3\\x=-4-3\end{array}\right.\Leftrightarrow\left[\begin{array}{nghiempt}x=1\\x=-7\end{array}\right.\)

Answer 4

b/135-|9-x|=35

\(\left|9-x\right|=135-35\)\(\left|9-x\right|=100\)\(\Rightarrow\left[\begin{array}{nghiempt}9-x=100\\9-x=-100\end{array}\right.\Leftrightarrow\nghiempt{\left[\begin{array}{nghiempt}x=9-100\\x=9+100\end{array}\right.}\Leftrightarrow\left[\begin{array}{nghiempt}x=-91\\x=109\end{array}\right.\)