a,47-(x+15)=21
(x+15)=47-21
x+15=26
x=26-15
tự tính
chúc là tốt
e: =>x-13=5 hoặc x-13=-5
=>x=18 hoặc x=8
g: =>|x+8|=22
=>x+8=22 hoặc x+8=-22
=>x=-30 hoặc x=12
i: =>x+3=0 và y-2=0
=>x=-3 và y=2
\(47-\left(x+15\right)=21\)
\(x+15=47-21\)
\(x+15=26\)
\(x=26-15\)
\(x=11\)
\(b,-5-\left(24-x\right)=-11\)
\(24-x=-5--11\)
\(24-x=-5+11\)
\(24-x=6\)
\(x=24-6\)
\(x=18\)
\(c,6-\left|x\right|=2\)
\(\left|x\right|=6-2\)
\(\left|x\right|=4\)
\(\left[{}\begin{matrix}x=4\\x=-4\end{matrix}\right.\)
\(d,6+\left|x\right|=2\)
\(\left|x\right|=6+2\)
\(\left|x\right|=8\)
\(\left[{}\begin{matrix}x=8\\x=-8\end{matrix}\right.\)
\(e,\left|x-13\right|=5\)
\(\left[{}\begin{matrix}x-13=5\\x-13=-5\end{matrix}\right.\)
\(\left[{}\begin{matrix}x=5+13\\x=-5+13\end{matrix}\right.\)
\(\left[{}\begin{matrix}x=18\\x=8\end{matrix}\right.\)
\(g,\left|x+8\right|+3=25\)
\(\left|x+8\right|=25-3\)
\(\left|x+8\right|=22\)
\(\left[{}\begin{matrix}x+8=22\\x+8=-22\end{matrix}\right.\)
\(\left[{}\begin{matrix}x=22-8\\x=-22-8\end{matrix}\right.\)
\(\left[{}\begin{matrix}x=14\\x=-30\end{matrix}\right.\)
\(h,\left|-x+8\right|=\left|1-8\right|\)
\(\left|-x+8\right|=7\)
\(\left[{}\begin{matrix}-x+8=7\\-x+8=-7\end{matrix}\right.\)
\(\left[{}\begin{matrix}-x=7-8\\-x=-7-8\end{matrix}\right.\)
\(\left[{}\begin{matrix}-x=1\\-x=15\end{matrix}\right.\)
\(i,\left|x+3\right|+\left|y-2\right|=0\)
\(\left[{}\begin{matrix}x+3=0\\y-2=0\end{matrix}\right.\)
\(\left[{}\begin{matrix}x=0-3\\y=0+2\end{matrix}\right.\)
\(\left[{}\begin{matrix}x=3\\y=2\end{matrix}\right.\)
