1: \(\Leftrightarrow2x-1-2x-6=3x-9\)
=>3x-9=-7
=>3x=2
=>x=2/3
2: \(\Leftrightarrow6x-2=4x-8-21x\)
=>-17x+8=6x-2
=>-23x=-10
=>x=10/23
3: \(\Leftrightarrow2\left(2x-1\right)-5\left(x+1\right)=0\)
=>4x-2-5x-5=0
=>-x-7=0
=>x=-7
4: \(\Leftrightarrow4x-2x-5=3\)
=>2x-5=3
=>2x=8
=>x=4
5: \(\Leftrightarrow7+x\cdot\dfrac{5}{3}-x+2=0\)
=>2/3x+9=0
=>2/3x=-9
=>x=-6