Question 81699
Equilibrium means Demand = Supply:
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D= -200p + 35,000
The supply equation is predicted to be
S= -p2 + 400p - 20,000
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-200p + 35,000 =  -p2 + 400p - 20,000
p^2-600p+55000=0
p = [600+-sqrt140000)]/2
p = [600+-374.17]/2
p = 487.08 or p=112.915
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Cheers,
Stan H.