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Jucimar_C
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Finding the function

Hi,

How can I find the equation of a segment given by 2 points? Example: a(8,5) and b(5,8)
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Finding the function


@Jucimar_C wrote:
Hi,

How can I find the equation of a segment given by 2 points? Example: a(8,5) and b(5,8)

Many methods.  Here's one that works great in CAS (not Home):

 

line((8,5),(5,8)) ---> y = -x+13

 

Be sure to type "line" in lowercase letters, or it won't work.

 

Here's a method that works in both Home and CAS:

 

simplify(lagrange([[5,8],[8,5]] ) ) ---> -x+13  (the "y=" is implied)

 

I hope one of these fits your needs.  Disclaimer: I don't work for HP. I'm just another Prime user.

-Joe-
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Finding the function

Hi!, Josimar_C:

 

If you needed know, the conceptual theory, of find, one equation, see ...

 

a(x1, y1), b(x2, y2) ---> a(8,5), b(5,8)

 

y= mx + b

 

m= (y2 - y1)/(x2 - x1)

 

m=(8 - 5)/(5 - 8)= -3/3 = -1

 

m= -1( x1- y1) ---> m= -1 (8,5)

 

y - y1= m( x - x1)

 

y - 5= - (x - 😎

 

y - 5= - x + 8

 

Then, add 5 in (y-5) and 5 in (-x+8)

 

y-5+5=- x + 8 + 5

 

y= - x +13

Kind Regards !.
Have a nice day !.
@Maké (Technical Advisor Premium - HP Program Top Contributor).
Provost in HP Spanish Public Forum ... https://h30467.www3.hp.com/
Axel_59
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Finding the function

On the HP50G, you can use DROITE. In RPL mode :

 

(8,5) (5,8) DROITE

 

 

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It took me 8 years to realize that was a french word... 🙂

TW

Although I work for the HP calculator group as a head developer of the HP Prime, the views and opinions I post here are my own.
Ciro_Bruno
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Finding the function

Hello Jucimar

 

Let me suggest you a procedure to be performed in Geometry App. Please take a look at the attached sequence of screenshots. They are in Portuguese, but I guess it won't be a hard time for you

 

1st) Type both points in Symb view (GA and GB). Then create a line (GC) passing by GA and GB. You can go to Plot view and see how it looks like.

 

2nd) Go to Num view, choose and empty entry, click on Edit soft button ("Editar") and then in Vars. Select GC and you'll see the line's equation. Check the box if you want to see the equation further in Plot view.

 

Now, you can move the points and you'll see the chance in the line and its equation.

 

Regards,

Ciro

 

Line equation 01.jpg1 create points and lineLine equation 02.jpg2 how they look likeLine equation 03.jpg3 Num - edit entryLine equation 04.jpg4 place the line referrenceLine equation 05.jpg5 check the box for Plot viewLine equation 06.jpg6 equation in Plot view

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