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-4 + x = 6
x - 6 = -12
x/5 + 3 = 2
5x - 7 = -12
Solve for r: 3r = 12
Solve for x: x ÷ 2 = 3
7 = x + 12
x - 2 = 5
r/5 - 6 = -1
-5x + 2 = 67
5y - 10 = -25
x/5 = 1
4 + x/7 = 2
2 - 4x = 14
Solve for the variable. 8 = y + 3
Solve for the variable. 8 = y - 3
4 - 2x = 10

7x+8y=-18, 4x-9y=-3 solve the system of equations

How to do this , and can some one explain

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?