Solve for z
z = \frac{63}{2} = 31\frac{1}{2} = 31.5
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2z-81=-18
Multiply both sides of the equation by 9.
2z=-18+81
Add 81 to both sides.
2z=63
Add -18 and 81 to get 63.
z=\frac{63}{2}
Divide both sides by 2.
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