2x-6=y and x+3=2y and -3x+y=9 hii i urgently need to know how to find the x intercepts of these :)

Twelve friends shared 8 small pizza equally.how many pizzas did each person get?

You can find the constant of proportionality by finding the ratio of

1- 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.2- 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 the first question?