I have a Spreadhset with the following representing two sides of a Triangle

Angle Length
Side1, 20 35
Side2, 45 30
Side3,


I need a formula to calculate the Angle (degrees) and Length for the third
Angle

TIA
C

angle3 = 180 - ( angle1 + angle2 )
side3 is a bit trickier, must be a formula out there somewhere on the net
though.
Will have a think about that...

"Cathy" wrote:

> I have a Spreadhset with the following representing two sides of a Triangle
>
> Angle Length
> Side1, 20 35
> Side2, 45 30
> Side3,
>
>
> I need a formula to calculate the Angle (degrees) and Length for the third
> Angle
>
> TIA
> C
>
>
>
>
>
>

See here:
http://www.ajdesigner.com/phptriangl...ion_side_a.php

Hth,
Merjet

Your data doesn't describe a triangle.

Angle Length
Side1 20 35
Side2 45 30
Side3

If you had:

Angle Length
Side1 20 35
Side2 30
Side3

Then the triangle would be:

Angle Length
Side1 20 35
Side2 17 30
Side3 143 61.65

======

If you had:

Angle Length
Side1 20 35
Side2 45
Side3

Then the triangle would be:

Angle Length
Side1 20 35
Side2 45 72.36
Side3 115 92.75


Sometimes, too much information isn't a good thing!


Cathy wrote:
>
> I have a Spreadhset with the following representing two sides of a Triangle
>
> Angle Length
> Side1, 20 35
> Side2, 45 30
> Side3,
>
> I need a formula to calculate the Angle (degrees) and Length for the third
> Angle
>
> TIA
> C

--

Dave Peterson

Some more info:

Law of Cosines:
http://en.wikipedia.org/wiki/Law_of_cosines

Law of Sines:
http://en.wikipedia.org/wiki/Law_of_sines

and maybe
Law of Tangents:
http://en.wikipedia.org/wiki/Law_of_tangents



merjet wrote:
>
> See here:
> http://www.ajdesigner.com/phptriangl...ion_side_a.php
>
> Hth,
> Merjet

--

Dave Peterson

And sometimes too little information....

The angle provided is not the angle of a corner. It is the angle of the line
(or direction the line is pointing in with 0 degrees being at horizontally
pointing up, 90 degrees pointing vertically to the right etc.)

Regards
C

"Dave Peterson" wrote in message
> Your data doesn't describe a triangle.
>
> If you had:
>
> Angle Length
> Side1 20 35
> Side2 30
> Side3
>
> Then the triangle would be:
>
> Angle Length
> Side1 20 35
> Side2 17 30
> Side3 143 61.65
>
That would contain the formula I would need, as I can calculate Angle by
deducting Angle1 from Angle2

Would be much obliged if you could share the formula used to calculate the
blanks in this example you showed.

Hi Cathy,

If this is a follow up to the post l helped you with earlier in the
week then you need to change these 2 lines:

TiltValue = Range("A1").Value / 6
Theta = (TiltValue / 60 ) * TwoPI

to:

TiltValue = Range("A1").Value
Theta = (TiltValue * (PI/180))

or:

TiltValue = Range("A1").Value / 6
Theta = Radians(TiltValue)

If you look up COS and RADIANS in Excel help you will get explanations
& examples. It saved me having to get out all those geometry books!

Regards

Michael

Thanks again for that Michael

It is not quite a follow on from the previous mail but forms part of the
same spreadsheet.

The previous mail was to enable a visual illustration of what was happening.
I did get your correction on changing the lines to show degrees and this
works a treat. I thank you dearly for this.

This part merely wants to calculate the values using formulaand display the
values in cell.

I will have to look at this over the weekend as I have to get out now before
the weather turns.

Have a nice day
C


"michael.beckinsale" <(E-Mail Removed)> wrote in message
news:04e73432-8a24-44df-a33e-(E-Mail Removed)...
>
> TiltValue = Range("A1").Value / 6
> Theta = (TiltValue / 60 ) * TwoPI
>
> to:
>
> TiltValue = Range("A1").Value
> Theta = (TiltValue * (PI/180))
>
> or:
>
> TiltValue = Range("A1").Value / 6
> Theta = Radians(TiltValue)
>
> If you look up COS and RADIANS in Excel help you will get explanations
> & examples. It saved me having to get out all those geometry books!

Sounds to me like you are doing simple Vector addition.

Just guessing of course, but a Vector (r, Theta) to (x,y,z) might be:
(Change Degrees to Radians, z is zero)

{r*Cos[d*Degree], r*Sin[d*Degree], 0}

Hence:

v1 = Vector[35, 20]

{35*Cos[20*Degree], 35*Sin[20*Degree], 0}

v2 = Vector[30, 45]

{15*Sqrt[2], 15*Sqrt[2], 0}


Add your x,y, & z 's together (z is zero)

The general equation from x,y,z to a Vector (r, Theta,z) is:

{Sqrt[x^2 + y^2], ArcTan[x, y], z}


If I cheat and use a math program...

v3 = CoordinatesFromCartesian[v1 + v2, Cylindrical]

{63.468467389538915, 0.5501802241799797, 0.}

Side: 63.468
Angle: 0.55 Radians

or 31.523 Degrees


{63.468467389538915, 31.52300481707432, 0.}

Again, just guessing.
--
Dana DeLouis



"Cathy" <(E-Mail Removed)> wrote in message
news:(E-Mail Removed)...
> And sometimes too little information....
>
> The angle provided is not the angle of a corner. It is the angle of the
> line (or direction the line is pointing in with 0 degrees being at
> horizontally pointing up, 90 degrees pointing vertically to the right
> etc.)
>
> Regards
> C
>
>