a. x - (17 - 8) = 5 + (10 - 3x)
x - 9 = 5 + 10 - 3x
x - 9 = 15 - 3x
x + 3x = 15 + 9
4x = 24
x = 24 : 4
x = 6
b. 25 - (30 + x) = x - (27 - 8)
25 - 30 - x = x - 19
-5 - x = x - 19
-5 + 19 = x + x
14 = 2x
14 : 2 = x
7 = x
c. |x + 5| = 7
\(\Rightarrow\left\{\begin{matrix}x+5=7\\-\left(x+5\right)=7\end{matrix}\right.\Rightarrow\left\{\begin{matrix}x=2\\-x-5=7\end{matrix}\right.\)
\(\Rightarrow\left\{\begin{matrix}x=2\\x=-12\end{matrix}\right.\)
d. x(x - 1) = 0
\(\Rightarrow\left\{\begin{matrix}x=0\\x-1=0\end{matrix}\right.\Rightarrow\left\{\begin{matrix}x=0\\x=1\end{matrix}\right.\)
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a) x-(17-8)=5+(10-3x)
x-9=5+10-3x
x-9=15-3x
x+3x=15+9
4x=24
x=6