Posted by Milia on Sunday, June 5, 2011 at 5:35am.
How would you tell if an equation is a funtion or not. I know that it has to have only one yvalue for every x...but how do you identify this in an equation (rather than a graph)
ie. y=1/2x7 (how do i tell if this is a funtion or not)?
Any help would be much appreciated :)

Math  Andy, Sunday, June 5, 2011 at 6:28am
when dealing with linear functions, the general formula is y= mx + c..where m is the gradient and c is the yintercept. To find the value of x simply make y = to zero.hence the equation(y=1/27) is a linear function because if substituted in the general formula,1/2 would be the gradient(since it is the value/coefficient of x),, c=7 and x=1.

Math  drwls, Sunday, June 5, 2011 at 6:28am
Please use parentheses where needed for clarity. I don't know if that is
1/(2x7) or (x/2) 7 or (1/2x) 7
In each case, y is clearly a function of x because there is one and only one y for each x. (Except possibly where a denominator vanishes) 
Math  Milia, Sunday, June 5, 2011 at 6:40am
thanks :)