For the first example we will program the 
Quadratic Formula
which is shown to the right of the screen.
This is a useful program that is used to find the 
roots or zeros of a quadratic equation in the 
form ax squared + bx + c = 0.
Let's begin programming.
Where you want to start is with the program 
button right here.
So let's select that.
We want to move to the right where it says 
NEW.
Right here it says 
Create New and we're going to select ENTER.
Now were going to name the program and we'll 
call it QUAD.
So we're gonna need to use the ALPHA key to 
operate all of these letters that are in green.
We could also use the Alpha Lock (A-LOCK)
which every key that you will select, will 
automatically give you the letter above that key. 
So let's do that.  Go 2nd Function
which every key that you will select, will 
automatically give you the letter above that key. 
So let's do that.  Go 2nd Function
ALPHA.
And that puts it in Alpha Lock mode-  It says A-
LOCK.
Now I'm going to type in QUAD.
Q...U...A...D, so that's the name of the program.
So now  let's select program again and then 
move over to I/O.
and what we want is number 2 for Prompt.
So I'll select number 2.
Now what we want to do is enter in the three 
coefficients for the quadratic equation
and that is a, b, and c. So let's type in A, so we'll 
go  ALPHA  A
separate it with a comma,
then B, ALPHA B, and separate it with a 
comma, 
and then ALPHA C. Then select ENTER.
Now let's enter in the discriminant,
which is in parentheses, 
b squared - 4ac,
and let's close the grouping symbol.
And then we're going to use a
new key and that is the store key (STO>). So 
we're going store the b squared - 4ac
into another variable.
So let's select store which is right here
and it puts a little arrow on the screen
and then we're going to select a letter that we 
want to store that particular value in.
Let's store that in D. So I'm going to go ALPHA
and then D.
Now select ENTER.
Let's go back to the program mode.
Select program and then we want to select 
number 1, the If statement.
Select ENTER
and
we want to say if this value right here,
the b squared - 4ac which is stored in D,
If D is less than zero.
So let's go  ALPHA and then D, and then to get 
the
inequality sign we're gonna go back to the
test mode.  You would have to go
2ND Function and then select the MATH key
and then number five is less than.
And we want to find out if D is less than zero, 
then select ENTER.
And then let's go back to the program mode
and number 2 is Then.
So let's select number 2, so we have an If-Then 
statement going on right now
and select ENTER.
We want the calculator to display  "No Real 
Solutions"
so what we need to do is selected ENTER
and then we're going to go back to program 
(PRGM) then we want to move over
to where it says I/O.
And then we want to use the command number 
3 Disp, meaning display.
So we'll select 3, and now what is it that we 
want the calculator to display?
Well right here, if D is less than zero, which is 
the b squared - 4ac,
then we want the calculator to display "No Real 
Solutions".
and remember the b squared - 4ac
is inside the square root symbol.
So if that's less than zero, you know you cannot 
take the square root of a negative value
in the real number system. So we're going to 
display
"No Real Solutions"
So we need to do that
by entering in some text in quotation marks.
 Let's go to 2ND Function and then turn on the 
Alpha Lock.
So 2ND Function ALPHA turns on the Alpha 
Lock. We'll enter in quotations which is right 
here
right above above the + key.
Then we're gonna type in "No Real Solutions".
right down here if you select 0, that enters in a 
space, and then Real
and then space again, select the 0 key, 
Solutions, 
and then we want to end this with a quotation so 
select the + key
and there we have it. Now select ENTER.
Then we want to go back to the program key,
move over to I/O,
then we want to look for the command Goto.
So scroll down
and there it is.  Select ENTER
and then we want to select number 1, 
and you'll see where that comes in, in a 
moment.
Then select ENTER.
We're gonna go back to program
and then we want to select
number 3 for the command Else.
Select ENTER.
Now let's type in each part of the Quadratic 
Formula.
You have to be very careful with this, so let's 
start out with a left hand parenthesis,
and then another left hand parenthesis,
and then -b, ALPHA B, + the square root
of D, and remember D is the discriminant- the b 
squared - 4ac. So let's just type in D,
ALPHA D, close the grouping symbol
and then we want to close all of this with a right 
hand parenthesis.
And that's divided by the quantity 2a, so 2 ALPHA 
A,
and then close the quantity.
And then that needs to be closed by a right hand 
parenthesis, so this is the beginning left had
parenthesis and then everything inside here 
needs to be closed with a right hand parenthesis
select ENTER. Now we're gonna do the same 
thing except we're gonna change this
plus symbol to a subtraction symbol because 
remember
so let's do that.
Now, we need to use the subtraction key right 
here not the negative key (-).
Now we need to use the subtraction key right 
here not the negative key (-).
Now we need to use the subtraction key right 
here not the negative key (-),
and then select ENTER.
Now, I purposely made a mistake here because I 
wanted to show you some basic editing.
So the first thing that I realized is that I needed to 
store each one of these computations
into memory. So I want to assign
this particular value to a letter E.  So let's move 
down right here and hit the store key
and let's store that in E,  so ALPHA  E.
Then we could just move down to the next line 
that and I need edit,
and I want to store this quantity in F. So hit the 
store key and then ALPHA  F.
Now, let's say that I wanted to insert a line
right here. So in other words this particular line 
shouldn't be here.
So is all I need to do is go to the beginning of the 
line, go 2ND Function, Insert, and then select 
Enter and you can see that it just shifted down 
this whole
statement to a new line, and here's the blank 
line. So you could go up
and then enter anything in that you want, so let's 
just enter in some nonsense...
And let's say that you wanna get rid of this line. 
So that's really easy you can just hit the CLEAR 
key
and then you would go ahead and selected the 
delete key (DEL),
and now we're back to what we want.
So those are just some basic editing features 
that you'll use most of the time.
OK
So now let's move down to the next line
right here. So after I stored the value in F,  I 
would just select ENTER and that's going to 
create a new line.
Alright,  so lets hit the program button and let's 
move over to the I/O
and then we want to display, so number 3.
And what do we want to display?  So were 
gonna enter in some text, so let's enter in 
"Solutions".
So let's use the Alpha Lock, 2ND Function 
ALPHA.
Remember anything we display we want in 
quotation marks and we'll type in "Solutions"...
OK
and then we want to close
any type of text in quotation marks if we're in the 
display mode, and there we have it.
Now, what do we want to display? Well we want 
to display the solutions. What are the solutions 
going to be?
Now, what do we want to display? Well we want 
to display the solutions. What are the solutions 
going to be? 
Well, remember we stored this 
in E and this in F. So we want to display E and F.
So I'm going to separate this with a comma.
If you notice right here you have a little A 
flashing,
that means you're still Alpha Lock mode so if I hit 
ALPHA again, it goes away.
Now I can select the comma,
and then enter in E, so ALPHA  E,
and then separate that with a comma, and then 
ALPHA  F, 
and then select ENTER.
Now remember we have that Goto 1...
let's just move up...
and there it is,  Goto 1. So we have to have a 
label for this because the Goto 1 searches for a 
label.
So we're going to select the program key
and then we're going to look for Lbl
so let's scroll down and there it is, number 9. So 
I can select ENTER
and then we want to put number 1 here
because we had Goto 1 and we want Lbl 1.
That's the end of the program, so now I'm going 
to go 2ND Function and QUIT.
Now if everything worked out right the notation
and the actual program, then we should be able 
to run this program and get some accurate 
results.
So, for the first example we're gonna go ahead 
and solve the quadratic equation
x squared -5x - 14 = 0.  So in this case a = 1,    
b = -5, and  c = -14.
So how do we run this program?
Well if we select program, we can see now that 
we have the name QUAD,
and remember we named this program QUAD 
so select ENTER.
It says prgmQUAD, select ENTER again,
now's it's asking us for the value of A.
So that is 1, select ENTER, then it asks for the 
value of B that's -5,
select ENTER,
and then it asks for the value of C and that's  
-14,
select ENTER.
An then it gives us our solutions...  7 and -2,
and right here it tells us that the program is 
done.
Now let's go to example number 2.
So we want to solve the quadratic equation 4x 
squared +11x - 20 = 0.
The value of  a is 4, b is 11, and c is -20.
So let's run the program again.
Now, is all we have to do is just select ENTER
and then it will repeat our prompts for  A, B, and 
C.
So  A is 4, ENTER,
B is 11, ENTER, and C is -20
select ENTER.
And here's our solutions:
x = 1.25 and x = -4.
These are also called the roots of the equation 
or the zeros of the equation.
Now, let's do one more example, which is
the equation 2x squared - 5x + 8 = 0.
In this case  a = 2, b = -5, and c = 8.
So again if I select ENTER, 
I can run the program. You could also back to 
the program button
and then you'll see the name  QUAD and then 
select ENTER.
and then you'll see the name  QUAD and then 
select ENTER.
And then you'll get program QUAD select 
ENTER again and then you'll input the values.
So  A = 2, B = -5, and C = 8, select ENTER,
and here it says "NO REAL SOLUTIONS".
So what that means is that
the discriminant, that b squared -4ac  was less 
than 0. Remember we assigned that
value to D, and if D was less than zero,
we wanted the calculator to display "NO REAL 
SOLUTIONS".
And there you have it.
This is a simple program to use when you need 
to find the zeros or the solutions for a quadratic 
equation using the quadratic formula.
