How do i locate the point of intersection of two lines graphs

[Guest]

I have a plot of two lines using excell which intersect at a point. I want to
locate the point of their intersection using excell and show the co-ordinates
of that point so that any body can see that i read that point from it.
Step by step procedurewould be helpful and i am using microsoft excel 2007.
Thanks.

 

[Bernard Liengme]

I will assume you have two straight lines - if not please tell me what they
are.

Let the lines follow the two functions
y1=m1x1+b1 and y2=m2x2+b2
Let the point of intersection be Y and X
Then m1X+b1=m2X+b2, giving X=(b2-b1)/(m1-m2)

In Excel terms,
X=(INTERCEPT(y-values2,x-values2)-INTERCEPT(y-values1,x-values1))/(SLOPE(y-values1,x-values1)-SLOPE(y-values2,x-values2))
and Y =SLOPE(y-values1,x-values1)*X+INTERCEPT(y-values1,x-values1)

Put these two formulas in cell A100 and B100
Select A1:B100 and Copy
Click chart; use Edit |Paste Special| specify New Series with X-value in
first cell
Click OK
Now the chart has the point of intersection as a marker.
best wishes

 

[Maria F]

How can I find the intersection between a logarithmic curve and a straight line?

Thanks.



Bernard Liengme wrote:

I will assume you have two straight lines - if not please tell me what they
30-Aug-07

I will assume you have two straight lines - if not please tell me what they
are

Let the lines follow the two function
y1=m1x1+b1 and y2=m2x2+b
Let the point of intersection be Y and
Then m1X+b1=m2X+b2, giving X=(b2-b1)/(m1-m2

In Excel terms
X=(INTERCEPT(y-values2,x-values2)-INTERCEPT(y-values1,x-values1))/(SLOPE(y-values1,x-values1)-SLOPE(y-values2,x-values2)
and Y =SLOPE(y-values1,x-values1)*X+INTERCEPT(y-values1,x-values1

Put these two formulas in cell A100 and B10
Select A1:B100 and Cop
Click chart; use Edit |Paste Special| specify New Series with X-value in
first cel
Click O
Now the chart has the point of intersection as a marker
best wishe
--
Bernard V Liengm
Microsoft Excel MV
www.stfx.ca/people/bliengm
remove caps from emai


Previous Posts In This Thread:

How do i locate the point of intersection of two lines graphs
I have a plot of two lines using excell which intersect at a point. I want to
locate the point of their intersection using excell and show the co-ordinates
of that point so that any body can see that i read that point from it
Step by step procedurewould be helpful and i am using microsoft excel 2007
Thanks.

I will assume you have two straight lines - if not please tell me what they
I will assume you have two straight lines - if not please tell me what they
are

Let the lines follow the two function
y1=m1x1+b1 and y2=m2x2+b
Let the point of intersection be Y and
Then m1X+b1=m2X+b2, giving X=(b2-b1)/(m1-m2

In Excel terms
X=(INTERCEPT(y-values2,x-values2)-INTERCEPT(y-values1,x-values1))/(SLOPE(y-values1,x-values1)-SLOPE(y-values2,x-values2)
and Y =SLOPE(y-values1,x-values1)*X+INTERCEPT(y-values1,x-values1

Put these two formulas in cell A100 and B10
Select A1:B100 and Cop
Click chart; use Edit |Paste Special| specify New Series with X-value in
first cel
Click O
Now the chart has the point of intersection as a marker
best wishe
--
Bernard V Liengm
Microsoft Excel MV
www.stfx.ca/people/bliengm
remove caps from emai



Submitted via EggHeadCafe - Software Developer Portal of Choice
Dr. Dotnetsky's Cool .NET Tips & Tricks # 12
http://www.eggheadcafe.com/tutorial...8968-ab20ab99320d/dr-dotnetskys-cool-net.aspx

 

[Bernard Liengme]

What is the equation of the logarithmic line? Different people use different
expression - what do you use?