5. 5+2x=2x+6
this is false. 5=6 !
6. 4(-8x+5)=-32x-26
-32x+20=-32x-26
this is false. 20=-26 !
7. -18-6k=6(1+3k)
-18-6k=6+18k
-6k-18k=6+18
-24k=24
k=-1
8. 8x+4(4x-3)=4(6x+4)-4
8x+16x-12=24x+16-4
8x+16x-24x=16-4+12
this is false. 0=24 !
9. 38+7k=8(k+4)
38+7k=8k+32
7k-8k=32-38
-k=-6
k=6
10. 3(1-3x)=5-(9x+2)
3-9x=5-9x-2
-9x+9x=5-2-3
0=0
x is all of real number