In fuction f(x)= 4(x^2-6x+ )+20, what number belongs in the blank to complete the square

The sum of 5consecutive even numbers is 100. what is the first number in this sequence?

You just purchased two coins at a price of $670 each. because one of the coins is more collectible, you believe that its value will increase at a rate of 7.1 percent per year, while you believe the second coin will only increase at 6.5 percent per year. if you are correct, how much more will the first coin be worth in 15 years?

Jeremy wants to determine the number of solutions for the equation below without actually solving the equation.