a)
\(6x+5=4x-7\)
\(\Leftrightarrow6x-4x=-7-5\)
\(\Leftrightarrow2x=-12\)
\(\Leftrightarrow x=-6\)
b)
\(-3\left(x-5\right)-1=2x-1\)
\(\Leftrightarrow-3x+15-1=2x-1\)
\(\Leftrightarrow-3x-2x=-1-15+1\)
\(\Leftrightarrow-5x=-15\)
\(\Leftrightarrow x=3\)
c)
\(30-5\left(3-x\right)=2x-3\)
\(\Leftrightarrow30-15+5x=2x-3\)
\(\Leftrightarrow5x-2x=-3-30+15\)
\(\Leftrightarrow3x=-18\)
\(\Leftrightarrow x=-6\)
a) 6x+5=4x-7
6x-4x=-7-5
2x =-12
x =-12:2
x =-6
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