An experienced ice skater spins on the ice, creating a perfect circle with a diameter of 8 feet. What is the circles radius?

Marcus needs to rewrite f(x) = x2 + 6x + 4 in vertex form.

Alonso walked with his friend andy one day, and wanted to compare their speeds. alonso walked 3 miles in one hour, and andy walked 2 miles in 2 hours. complete the table to graph the relationship for each person.

Steve wants to develop a way to find the total cost of any item including sales tax. the sales tax in his city is 6%. his friend jenna writes the expression x + 6x where x is the cost of the item. explain whether her expression is correct based on the situation.