If you add a multiple of 420 to 301 you get the next number.
So 7*420+301=3241 is a number that applies.

I also noticed you have not included a Read line, char, key, or something at the end. So it might be that all is happening but as soon as it does it disappears...

Have you recompiled?

If in the while loop leave out the initialisation of number=0; it should work, now you are always testing zero.

The point of intersection : solve two linear equations in y and x

From what I see you already have this should not be so hard.
For instance if two lines are parralel they must have the same slopes, if they also share a point they must be collinear.

If you can OO compare cars it should be easy to compare lines.
What have you got so far?
EDIT: sorry this was just posted after yours...

The program wont crash, but as long as you don't type YES,Yes,yES etc. you will stay in the do...while loop.

You would write it as 6.83783E-3

employeeName = input.nextLine(); <--here input of emp
{

// read value for hourly wage<--here hoursWorkedInWeek is not input and still=0.0
if...

Why is it that the only thing you input is an employeeName?
What about the rest where is that put in the programs variables?

A statement after a break statement is unreachable.

Come on guys calm down!
There is more than enough shooting in the world!
Be friends!
Make love!

At that moment hoursWorkedInWeek is equal to 0.0.
You told it to be 0.0 before entering the...