Why Isn't the Energy Equation Ef=kx^2/2−mgx?

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The mass is released at height h above the spring, how far will the spring move? Ei=mgh,Ef=kx2/2+mgx...why the second equation isn't Ef=kx2/2−mgx? Since it is below the "zero".
 

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Your equation for Ef is correct.
 
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