What is 16x4 - 100y4 factored completely? (4x2 + 10y2)(2x - 5y)(2x + 5y)
(2x - 5y)2 (2x + 5y)
16(x2 - 5y2)(x2 + 5y2)
4(2x2 - 5y2)(2x2 + 5y2)

When a valve is open 281 gallons of water go through it in one hour the number of gallons that would go through in 94 hours is

In cents, what is the least total amount that cannot be obtained by using a combination of fewer than eight coins from a collection of pennies, nickels, dimes and quarters?

Sandra wants to evaluate 2 cot her work is shown below. what did she do wrong?