Surface area of a prism 18x24x30x7

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.

We just started the introduction into circles and i have no idea how to do this.

Rewrite the following quadratic functions in intercept or factored form. show your work. y = 4x^2 - 19x- 5