Oder the least to greatest: -3, -10, -1 please helppp

Which one ? is the answer and how to find this answer

Which equation results from adding the equations in this system? x+6y=9 and -x+2y=-15

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.