Two variable equation solver

[psburton]

I have made some equation solving programs for my Algebra II class, but the limitations of single variable solving (x+1=3, etc.) is embarrassing. Any ideal on making dual variable solvers? It couldn't use trial and error because that would take forever...
but and help or comments would be appreciated.

[Xphoenix]

You mean in BASIC?
The 68Ks come with a Simultaneous Equation Solver, if thats what you mean.
If you have a Z80 (excluding 85/86), there's an app called PlySmlt. I used to have. It's also a simultaneous equation solver, but there's one other thing in it. Let me try to find it.

EDIT:
Here:http://education.ti.com/educationportal/...83_84.html

[Vlad]

Do you know about Row-reduced Echelon Form or solving simultaneous equations by inverse matrices?

[psburton]

Vladik Wrote:Do you know about Row-reduced Echelon Form or solving simultaneous equations by inverse matrices?

Of course not! I am a tenth grader! lol

[bfr]

You could symbolically solve:

ax+by=c
dx+ey=f

for x and y in terms of a,b,c,d,e, and f, and then base your program off of that.

You could also take a look at Cramer's rule.

Vladik: "I have made some equation solving programs for my Algebra II class"

[Vlad]

Well, if he is in 2 Algebra, then he probably would not understand Cramer´s rule... I mean, that is abstract algebra and universal algebra, not elementary algebra... Nevertheless, he should take a look at that.

Hmm. You should get your math teacher to explain Row-reduced Echelon Form to you. It is a very fast (for a calc, that is) method to solve these kinds of problems. I would explain it, but perhaps another day. I don´t really feel like it today.

EDIT: Now that I think of it, Cramer´s rule is more abstract algebra than universal algebra...

[bfr]

Cramer's Rule isn't that difficult to understand - it's basically:

ax+by=e
cx+dy=f

x=(cd-bf)/(ad-bc) y=(af-ec)/(ad-bc)

[psburton]

We've already done Cramer's Rule. It wasn't till now that I saw you could utilize that.

[pandora]

bfr Wrote:Cramer's Rule isn't that difficult to understand - it's basically:

ax+by=e
cx+dy=f

x=(cd-bf)/(ad-bc) y=(af-ec)/(ad-bc)

x=(bf-ed)/(ad-bc)
y=(af-ec)/(ad-bc)