Suppose we know that two variables (x and y) are related such that y = -3 times x.
What does the statement y = -3 times x mean?

Question

Suppose we know that two variables (x and y) are related such that y = -3 times x.
What does the statement y = -3 times x mean?

a_clan · Answer

As the value of x increases on the positive side, y decreases on the negative side thrice in magnitude.
Similarly, when x decreases on the negative side, y increases on the positive side thrice in magnitude.

anonymous · Answer

So do i have to do something to the equation or is that like THE equation?

a_clan · Answer

My explanation can be understood by substituting values of x in the equation and finding corresponding values of y.
For example, when x= 1, y =-3
                   when x becomes 2, y becomes -6
                   when x becomes 3, y becomes -9  and so on.
 It means as the value of x is increasing in the positive , value of y is decreasing in the negative thrice.

anonymous · Answer

Thats confusing but thanks..

a_clan · Answer

You need to know that x and y are variables. Variables are those whose values are not fixed; they change. When you are given a function (equation) containing x and y, it means x and y are co-related. On changing the value of one variable, the value of other variable will change by itself. The same is happening in the above case. You are changing the values of x and obtaining different values of y.  
     The function(equation) gives the amount by which the value of one variable will change with respect to others. That means in different cases, there can be different functions between x and y. 
   Hope it helps. However if the confusion persists, I will suggest that you start by understanding "Relations and Functions" first. Thanks.