Explicație pas cu pas:
d)-3(-x+2)=-12
minus ori minus = plus
3x-6=-12 | +6
trece in partea cealalta cu semn schimbat
3x=-6/3
x=-2
j)x+2×(x-3)=0
x+2x-6=0
x+2x=0 | +6
3x=6
x=6/3
x=2
k)2x-(-4-3x)=9
2x+4+3x=9 | -4
5x=5
x=5/5
x=1
l)x+2x-3x=0
3x-3x=0
0=0
m)3(x+2)=-2(x+1)-17
3x+6=-2x-2-17
3x+2x=-19-6
5x=-25
x=-25/5
x=-5
n)-5(4+3x)+8x-4=2(x-3)
-20-15x+8x-4=2x-6
-20-7x-4=2x-6
-24-7x=2x-6
-7x-2x=24-6
-9x=18
x=18/-9
x=-2