Question

(-8z+8)-(2z+7)

Answer 1

(-8z+8)-(2z+7)
-8z+8-2z-7
-10z+1

Answer 2

cannot set equal to 0 because it is not an equation just an expression

Answer 3

(-8z+8)-(2z+27)
-8z+8-2z-7
-8z-2z+8-7
-10z+1

You cannot simplify this any further I don't think. If I haven't answered your question then please type the question and not just the equation you were supposed to solve :)

Answer 4

@tiffany.myers95