# What does the equation xy=k represent?

1. Jul 3, 2008

### svigneshkumars

What does the eqn xy=k represent?

2. Jul 3, 2008

### arildno

Re: xy=k

It depends upon the interpretation of your symbols x,y and k.

3. Jul 3, 2008

### kts123

Re: xy=k

In many cases, that will represent a function (though I'm used to seeing z insteak of k.)
f(x, y) = k. In your case, f(x, y) takes the two inputs (x and y, obviously) and multiplies them together. k is called the output, x and y are inputs. Most people will remember seeing f(x) = y in highschool, in this case f() has two variables intead of one. As Arlidno mentions, the interpretation will vary. x may represent height and y may represent width, hence k would represent the area of a square-ish object.

4. Jul 3, 2008

### Quantumduck

Re: xy=k

Well, if you solve it for y, then you get: y = k/x. This is an inverse variation.

It could be as simple as that.

5. Jul 3, 2008

### mathman

Re: xy=k

Assuming x and y are variables and k is a constant, the graph will be a hyperbola.

6. Jul 3, 2008

### arildno

Re: xy=k

Assuming "xy" is a constant, the k-graph is either a straight line, assuming a (k,l)-coordinate system to speak out from.