You can put this solution on YOUR website! I think one of the signs should be a +, but Iam not sure which one.
-3(2z-8)=10z+16
-6z+24=10z+16
-6z-10z=16-24
-16z=-8
z=1/2
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-3(2z-8)+10z=16
-6z+24+10z=16
4z=-8
z=-2
================
I hope one helps you.
:)