The quantity demanded x for a certain brand of MP3 players is 100 units when the unit price p is set at $100. The quantity demanded is 1100 units when the unit price is $50. Find the demand equation.P=

Answer:x = 2100 - 20pStep-by-step explanation:Let the quantity demanded be 'x'unit price be 'p'thus, from the given relation in the question, we havep (100) = $100and,p (1100) = $50now, from the standard equation for the line [tex]\frac{\textup{p - p(100)}}{\textup{x - 100}}[/tex]  = [tex]\frac{\textup{p(1100) - p(100)}}{\textup{50 - 100}}[/tex] or[tex]\frac{\textup{p - 100}}{\textup{x - 100}}[/tex]  = [tex]\frac{\textup{50 - 100}}{\textup{1100 - 100}}[/tex] or1000 × (p - 100) = - 50 × ( x - 100 )or20p - 2000 = - x + 100orx = 2100 - 20p