In a Survey It Was Determined That the Demand Equation

Short Answer

In a survey it was determined that the demand equation for VCRs is given by
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The demand equation for blank VCR tapes is given by
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where p and q denote the unit prices, respectively, and x and y denote the number of VCRs and the number of blank VCR tapes demanded each week. Determine whether these two products are substitute, complementary, or neither.