Could use some help please

Choose the correct slope of the line that passes through the points (1, -3) and (3, -5)

The border line of the linear inequality 4x + 7y < 5 is dotted true or false?

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?