1, (x+3) :(-6)=2
(x+3) = 2×(-6)
x+3 = (-12)
x = (-12) +3 = (-9)
2,20+ (x+4)= 15
x+4 = 15-20=-5
x = -5-4=-9
3, 14-(3-x)=20
3-x = 14-20=-6
x = 3-(-6)=3+6=9
4, -2(x+1)+8=〖(-4)〗^2019 ∶ 〖(-4)〗^2017
-2(x+1)+8=〖(-4)〗^(2019-2017) = (-4)∧2= 16
-2(x+1) = 16-8=8
(x+1) = 8:(-2) = -4
x = -4-1 =-5
5, (-2x+6):3=-〖(-2)〗^2
(-2x+6):3= -4
-2x+6 = (-4)×3 = -12
-2x = -12-6=-18
x = (-18):(-2) =9
6, 3(2-x)-6=-15
3(2-x) = -15+6 =-9
2-x = (-9):3 = (-3)
x = 2-(-3) =5
7, 2x+9= 7
2x = 7-9 = (-2)
x = (-2):2 = (-1)