I can draw a line chart o/k but not a graph that starts at x=0,y=0.
Obviously, this is because the x axis in Excel is divided up into domains,
from 0 to 1, 1 to 2, 2 to 3, etc and x values are shown as mid-ordinate
values. However, I want to plot the line graphs y=39000+3x, and y=2800+2x and
show the crossoverpoint at 61000 where it should be, not at 61500!

You need to make an XY chart
XY chart can also have lines on them
Line charts are used when the x-values are categories (which could be
numbers like zip codes but are not truly numeric in that no one ever does
moth with them), XY are used when the x-values are actual numeric values
best wishes
--
Bernard V Liengme
Microsoft Excel MVP
http://people.stfx.ca/bliengme
remove caps from email

"ColinC" wrote in message
...
I can draw a line chart o/k but not a graph that starts at x=0,y=0.
Obviously, this is because the x axis in Excel is divided up into domains,
from 0 to 1, 1 to 2, 2 to 3, etc and x values are shown as mid-ordinate
values. However, I want to plot the line graphs y=39000+3x, and y=2800+2x
and
show the crossoverpoint at 61000 where it should be, not at 61500!

I don't understand what you are saying about a cross-over at 61000 or 61500.
From simple algebra the crossover has to be at X=2800-39000, i.e. X=-32000,
and hence Y=-69600.

If you are trying to look at that sort of data, then I'm surprised that
you've used a line chart. Don't you want an XY chart? Have you been
confused by Excel's misleading naming system for the chart types?
--
David Biddulph


"ColinC" wrote in message
...
I can draw a line chart o/k but not a graph that starts at x=0,y=0.
Obviously, this is because the x axis in Excel is divided up into domains,
from 0 to 1, 1 to 2, 2 to 3, etc and x values are shown as mid-ordinate
values. However, I want to plot the line graphs y=39000+3x, and y=2800+2x
and
show the crossoverpoint at 61000 where it should be, not at 61500!

Hi David. It's for a simple little project I've been given in uni, plotting
the economics of buying a machine costing £39000 that machines parts at £2
/part, or a machine costing £28000 that costs £3 per part to operate. up to
11000 parts, the cheaper machine wins, but after that, the dearer machine
scores. I am plotting cost on the y axis and numbers of parts on the x axis
for both machines. The lines should cross at 11000 parts.
Anyway, thanks David and Bernard for the tip on XY charts, I'll try it.
ColinC

"David Biddulph" wrote:

I don't understand what you are saying about a cross-over at 61000 or 61500.
From simple algebra the crossover has to be at X=2800-39000, i.e. X=-32000,
and hence Y=-69600.

If you are trying to look at that sort of data, then I'm surprised that
you've used a line chart. Don't you want an XY chart? Have you been
confused by Excel's misleading naming system for the chart types?
--
David Biddulph


"ColinC" wrote in message
...
I can draw a line chart o/k but not a graph that starts at x=0,y=0.
Obviously, this is because the x axis in Excel is divided up into domains,
from 0 to 1, 1 to 2, 2 to 3, etc and x values are shown as mid-ordinate
values. However, I want to plot the line graphs y=39000+3x, and y=2800+2x
and
show the crossoverpoint at 61000 where it should be, not at 61500!

So when you said y=39000+3x you meant y=39000+2x
and when you said y=2800+2x you meant y=28000+3x ?

Now all is clearer!
--
David Biddulph

"ColinC" wrote in message
...
Hi David. It's for a simple little project I've been given in uni,
plotting
the economics of buying a machine costing £39000 that machines parts at £2
/part, or a machine costing £28000 that costs £3 per part to operate. up
to
11000 parts, the cheaper machine wins, but after that, the dearer machine
scores. I am plotting cost on the y axis and numbers of parts on the x
axis
for both machines. The lines should cross at 11000 parts.
Anyway, thanks David and Bernard for the tip on XY charts, I'll try it.
ColinC

"David Biddulph" wrote:

I don't understand what you are saying about a cross-over at 61000 or
61500.
From simple algebra the crossover has to be at X=2800-39000, i.e.
X=-32000,
and hence Y=-69600.

If you are trying to look at that sort of data, then I'm surprised that
you've used a line chart. Don't you want an XY chart? Have you been
confused by Excel's misleading naming system for the chart types?
--
David Biddulph


"ColinC" wrote in message
...
I can draw a line chart o/k but not a graph that starts at x=0,y=0.
Obviously, this is because the x axis in Excel is divided up into
domains,
from 0 to 1, 1 to 2, 2 to 3, etc and x values are shown as mid-ordinate
values. However, I want to plot the line graphs y=39000+3x, and
y=2800+2x
and
show the crossoverpoint at 61000 where it should be, not at 61500!

Hi,

You problem is that you gave us the wrong formulas, they should be:

=39000-3*A2
=28000-2*A2

If your X values are in the range A2:A20 and start at 0 and are incremented
1000 you will get the intersection at 11,000.

If this helps, please click the Yes button.

cheers,
Shane Devenshire

"ColinC" wrote:

Hi David. It's for a simple little project I've been given in uni, plotting
the economics of buying a machine costing £39000 that machines parts at £2
/part, or a machine costing £28000 that costs £3 per part to operate. up to
11000 parts, the cheaper machine wins, but after that, the dearer machine
scores. I am plotting cost on the y axis and numbers of parts on the x axis
for both machines. The lines should cross at 11000 parts.
Anyway, thanks David and Bernard for the tip on XY charts, I'll try it.
ColinC

"David Biddulph" wrote:

I don't understand what you are saying about a cross-over at 61000 or 61500.
From simple algebra the crossover has to be at X=2800-39000, i.e. X=-32000,
and hence Y=-69600.

If you are trying to look at that sort of data, then I'm surprised that
you've used a line chart. Don't you want an XY chart? Have you been
confused by Excel's misleading naming system for the chart types?
--
David Biddulph


"ColinC" wrote in message
...
I can draw a line chart o/k but not a graph that starts at x=0,y=0.
Obviously, this is because the x axis in Excel is divided up into domains,
from 0 to 1, 1 to 2, 2 to 3, etc and x values are shown as mid-ordinate
values. However, I want to plot the line graphs y=39000+3x, and y=2800+2x
and
show the crossoverpoint at 61000 where it should be, not at 61500!