A box is created from a rectangular piece of cardboard 20 centimeters by 28 centimeters by cutting a square from each corner and folding up the sides, as shown in the diagram. Write an expression for the volume of the box as a polynomial in standard form.

1- is the product of two rational numbers irrational or rational? first, make a hypothesis by multiplying two rational numbers. then, use variables such as x=a/b and y=c/d and the closure property of integers to prove your hypothesis. 2- what do you think the product of a nonzero rational number and an irrational number is? is it rational or irrational? make use of variables, the closure property of integers, and possibly a proof by contradiction to prove your hypothesis. 3- why do we have to specify that the rational number must be nonzero when we determine what the product of a nonzero rational number and an irrational number is? if the rational number were 0, would it give us the same result we found in part b?

Which of the following is best modeled using a linear equation y=ax+b, where a is less than 0?

Consider the diagram. lines e and c can be described as