# values of x below the x axis

• Dec 8th 2012, 05:34 PM
rcs
values of x below the x axis
May i know what this problem all about... i just can imagine how it looks like but l as the values of x, how it is being done? how to write as set for the values of x? can anybody help?

For what values of x is the graph of 2x – 3y – 4 = 0 below the x – axis?

​thanks a lot
• Dec 8th 2012, 08:18 PM
alexagak
Re: values of x below the x axis
For the graph to be below the x-axis you need to havey<0.

So solve for y to get y=(2x-4)/3 and proceed to find the values of x for which the equation yields values less than 0.

As an example of how to express a set of (real) values, if you find that b<x<a [a,b are arbitrary constants] then the set of values x must belong to is (b,a).
• Dec 8th 2012, 08:28 PM
rcs
Re: values of x below the x axis
will i think it should be done this way

x = (- infinity , 2)

can anybody correct my work if it's not right.

thanks
• Dec 8th 2012, 08:58 PM
alexagak
Re: values of x below the x axis
you are correct