What is the slope of the line perpendicular to the line 4x-3y+12=0?

Which is the equation of an ellipse with directrices at x = ±4 and foci at (2, 0) and (−2, 0)?

How do i put 3(x+7) in distributive property

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?