Algebra I: Strand 3. Quadratic and Other Nonlinear Functions; Topic 2. Quadratics and
Solutions; Task 3.2.5
1
TASK 3.2.5: PARAMETER CHANGES FROM GRAPHS — THE AUTOBIOGRAPHY OF A CAT
The presenter will read the Cat story using the graphing calculator program as an
illustration. Participants then will create their own stories and illustrate their stories
using parameter changes with quadratic functions by modifying the graphing calculator
program.
Once upon a time I was a nice normal cat; ENTER . One day while lounging (typical
cat style) in the shade of an oak tree in my family’s back yard, I waited. Ever alert to the
dangers that lurk outside, I suddenly sensed movement. Nonchalantly, I cracked open
one eye and observed a sneaky shadowy mouse preparing an attack on my owner’s castle.
Quick as a flash, I was up tracking the mouse and fulfilling my role as protector of the
castle.
The mouse was fast and sneaky, but no match for me. I chased the little rodent for miles,
going far north east of my home, ENTER and continued the hunt as darkness
approached. Finally, I felt I had maneuvered the threat far enough from my home. As I
paused to rest, I realized that I now was lost. I felt a wave of sadness overtake me and I
became a sad cat. ENTER
I roamed the area trying to get my bearings when I came upon a major highway. Not
wanting to end up a flat cat ENTER I decided not to cross and to find another way
home. Now it was so late I would miss dinner! Missing a meal – not much can be worse
for a cat. Time passed, my paws became sore from traveling; hunger and malnutrition
were beginning to weaken my prime feline physique. Just when I thought it could get no
worse, the rain came. Now I was truly a sad, low, skinny cat. ENTER
As the hours turned into days, the days into weeks and the weeks into months my sadness
deepened and I became very low. ENTER During my travels I made several new
friends. My new companions taught me many survival skills. I became an expert at
raiding trash cans and chasing field mice. Soon I became a little happier cat. ENTER I
began to notice that I was putting on weight and my spirits were rising. ENTER Time
passed and places on my journey began to look more familiar. One day I looked around
and there I was – back home. Now I was once again a nice normal cat.
ENTER However, I was no longer alone, I had not 1, ENTER not 2, ENTER not
even 3, ENTER
but ENTER 4 babies with me.
November 23, 2004. Ensuring Teacher Quality: Algebra I, produced by the Charles A. Dana Center at The
University of Texas at Austin for the Texas Higher Education Coordinating Board.
1
Algebra I: Strand 3. Quadratic and Other Nonlinear Functions; Topic 2. Quadratics and
Solutions; Task 3.2.5
2
Calculator Program for “The Autobiography of a Cat”
:ZStandard
:FnOff
:DrawF 3x2
:Pause
:ClrDraw
:DrawF 3(x – 3) 2 + 2
:Pause
:ClrDraw
:DrawF −3(x – 3) 2 + 2
:Pause
:ClrDraw
:DrawF .4x /((x ≤ 3)(x ≥ -3))
:Pause
:ClrDraw
:DrawF -18(x + 3)2 − 1
:Pause
:ClrDraw
:DrawF -25(x + 4)2 − 5
:Pause
:ClrDraw
:DrawF 18 (x + 4) + 2
:Pause
:ClrDraw
:DrawF .5(x + 2)2 + 2
:Pause
:ClrDraw
:DrawF x2
:Pause
:DrawF (x – 4)2 − 3 / ((x ≤ 6)(x ≥ 2))
:Pause
:DrawF (x + 3)2 − 3 / ((x ≤ −1)(x ≥ −5))
:Pause
:DrawF (x + 6)2 − 5 / ((x ≥ −8)(x ≤ −4))
:Pause
:DrawF (x -6)2 − 5 / ((x ≤ 8)(x ≥ 4))
November 23, 2004. Ensuring Teacher Quality: Algebra I, produced by the Charles A. Dana Center at The
University of Texas at Austin for the Texas Higher Education Coordinating Board.
2
Algebra I: Strand 3. Quadratic and Other Nonlinear Functions; Topic 2. Quadratics and
Solutions; Task 3.2.5
3
Technology notes
Steps to programming the calculator:
Turn calculator on
Press PRGM Key
→to highlight NEW
Press ENTER (notice the cursor is blinking meaning the calculator is in Alpha
mode and will type letters) type CAT and ENTER
The “:” indicates a command line. All commands must begin with the colon.
To find ZStandard, press zoom 6 ENTER for a new
command line.
To find the FnOff press VARS → #4 ENTER ;
press #2 ENTER for a new command line.
Three more keys are needed for this program.
To paste DrawF – press 2nd PRGM to access the draw menu
#6 – on the same line type 3x2 then hit ENTER key.
To paste the Pause command press PRGM, and under the
CTL (control) list arrow down to #8. Pause and hit ENTER .
To paste ClrDraw press2nd PRGM to access the draw menu
#1.
November 23, 2004. Ensuring Teacher Quality: Algebra I, produced by the Charles A. Dana Center at The
University of Texas at Austin for the Texas Higher Education Coordinating Board.
3