PLZ HELP! (Simplify) 1.) (5/7)+5(3a-4b)-(7a+12b)

2.) 2.4+5.4q-4.5q+3.6

3.) (13/4)x-8y-(5/4)x+7y+5

4.) 5x(3-12x)-3(4-20x2)

5.) (5/7)a2+13-(5/7)a-3

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?