\(\text{1/ (2x - 5) +17 =6}\\ 2x-5=6-17\\ 2x-5=-11\\ 2x=-11+5\\ x=-6:2\\ x=-3\)
\(\text{2/ 10 - 2(4 - 3x) = - 4}\\ 2\left(4-3x\right)=10-\left(-4\right)\\ 2\left(4-3x\right)=14\\ 4-3x=14:2\\ 4-3x=7\\ 3x=4-7\\ x=-3:3\\ x=-1\)
\(\text{3/- 12 +3(- x + 7) = -18}\\ 3\left(-x+7\right)=-18-\left(-12\right)\\ 3\left(-x+7\right)=-6\\ -x+7=-6:3\\ -x+7=-2\\ -x=-2-7\\ -x=-9\\ x=9\)