The Demand Equation for a Certain Brand of Metal Alloy

Short Answer

The demand equation for a certain brand of metal alloy audiocassette tape is , where x represents the number (in thousands) of ten-packs demanded each week when the unit price is $p. How fast is the quantity demanded increasing when the unit price/ten-pack is $11 and the selling price is dropping at the rate of $.18/ten-pack/week? Round the answer to the nearest integer.
Hint: To find the value of x when p = 11, solve the equation for x when p = 11.
Increasing at the rate of __________ ten packs/wk.