IF I HAVE TWO equations 5x+8y=54, AND -9x+y=26 how do i solve

You have to use Y Editor to define functions on the both sides of the equation and then graph it. Finally option is F5: Intersection.
See captured images for equation 5x+10=-2x-7, y1=5x+10, y2=-2x-7 and x=-17/7

There are a few routines to solve simultaneous LINEAR equations that are embedded in the Operating system of the calculator.

1. solve(
   
2. Simult(

However if you are looking for the simultaneous equation solver application, you can download it from the TI website. Here is the link

If you need download and install instructions, you will find them here.

Hello,

Sorry, but what you wrote is not an equation but a polynomial expression. You want to solve the equation x^4+5x^3-3x^2-43x-60 =0.

The solve( command, can only be used with real numbers.
The solve( is available through the CATALOG : [2nd][CATALOG], scroll down till you reach the command. Highlight it and press [ENTER]. The command echodes on main screen as solve( .
You complete the command by entering the expression (not the equation), the name of the variable you solve for, the initial guess , and { lower limit, upper limit} between curly brackets, and the closing parenthesis.
Exemple:
solve (x^4+5x^3-3x^2-43x-60 , x,0 {-5,0} ) [ENTER]
should give you the negative root,
solve (x^4+5x^3-3x^2-43x-60 , x,0 {0,5} ) [ENTER]
should give you the positive root.

It is implied that the expression is 0, so you should not insert =0, otherwise you get an error. Here for the lower limit is -5 you must use the change sign symbol (-) under the 3 key, not the regular MINUS.

You may ask how I knew that there were two roots when the equation is a quartic? By first graphing it to have an idea about where the roots lie and how many there are. You should always do that to speed up the search.

There is another way to zoom in on the roots: by drawing the graph and using the tools accessible under the [2nd][CALC] menu, namely the option [2:Zero]
The resolution of the TI83/84 is not good enough for this function that grows too fast, but I am inserting a picture of the curve from another calculator with a much better resolution.



Hope it helps.

Hello,
Sorry this calculator cannot solve equations. It does not have the program. It does not know how to do those things. However it can calculate. Before you can use the calculator you must prepare all yourself. When you have solved the problem, you ask the calculator to compute the value of what you found.

Let us clean the equation a bit
2(x-4) -5x=-5
Get rid of the parentheses 2(x-4) becomes 2x-2*4=2x-8 .Put that result where it was in equation
2x-8 -5x=-5
Group together the terms that have x in them 2x-5x=-3x
Then
2x-8-5x=-5, becomes -3x-8=-5
You want to isolate the term with x (have it on one side, and the others on the other side) -3x= -5 -(-8)= -5+8 =3.

The equation becomes
-3x=3 Thus -x=3/3=1 and x=-1.
In general you would have obtained x= (some number/some other number) and that is where the calculator would intervene.

Hope it helps.

i think there are programs but with something as simple as that you should be able to work it out manually....
3x+25-5x=5x-5x
-2x+25-25=0-25
-2x=-25
x=25/2 or 12.5

This book is what I used to help learn how to solve mesh circuits. A high education level helps. You just set it up as you see it in a simultaneous equation.

Electrical Engineering Applications with the TI-89
Electrical Engineering students will find the 70 topics covered in this book provide in-depth analyses of how to solve many common engineering problems using the powerful CAS system of the TI-89.
Author(s) - David R. Voltmer and Mark A. Yoder
[email protected]

x^2+5x+7 won't factor any more.. if you're trying to solve it, do:

solve(x^2+5x+7=0,x)

Srry my friend the ti 83 is no magnificent Ti-89. meaning: you have to solve it yourself. There is a method for graphing though. Set the equation equal to zero and then plug the stuff on the other side of the equation into a graph by pressing y= and then typing it in. Then hit graph. Wait for the graph and then hit 2nd calc and select zeros. Bring your cursor using hte arrow keys close to where the line hits the x axis and press enter and then do the same except to the right of that point and then press enter twice and it will display the y which should be the answer
There are quadratic formulas for calculators programmed in tibasic for the calc but other than that there is no way to solve it

Type it like this: solve( equation1 and equation2 and moreEquations, {list of variables to solve for})

Put all of your equations right after the opening parenthesis separated by the word and, then a comma, then within curly braces each variable you want to solve for each separated by a comma.

Just plug in one side of the equation and find the answer. Then plug in the other side and compare answers.