To solve 35-19,jack used 35-20.what did he do next?

What is the gcf of 20c^3-5c^4+30c^6

Arestaurant offers delivery for their pizzas. the total cost the customer pays is the price of the pizzas, plus a delivery fee. one customer pays $23 to have 2 pizzas delivered. another customer pays $59 for 6 pizzas. how many pizzas are delivered to a customer who pays $86?

What is the maximum of the sinusoidal function