Formal definition to the word “markup”

Answer this question, only if you know the answer. 30 points and brainliest!

What is the slope simplify your answer and write it as a proper fraction, improper fraction, or integer

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.