Suppose the supply and demand for a certain textbook are given by supply p = 5 9 demand p 59 5 + 30 , where p is the price and a is the...

I keep getting the wrong answer. Could someone help with this? Thanks

Suppose the supply and demand for a certain textbook are given by supply p = 5 9 " demand p59 5 + 30 , where p is the price and a is the quantity . Find the demand quantity andthe supply quantity at a price of $20The number of books that are demanded at a price of $20 isand the number of books supplied at a price of $20 is( Round to the nearest whole number as needed . )