Program Quad

ClrHome
Disp "   aX^2+bX+c=0"
Disp "----------------"
0-->R
Disp "ENTER A"
Prompt A
Disp "ENTER B"
Prompt B
Disp "ENTER C"
Prompt C
If A=0
Then
Disp "A CANNOT BE ZERO"
Stop
End
((B^2)-(4AC))-->D
If D>=0
Then
(((-B)+(sqrtD))/(2A))-->E
(((-B)-(sqrtD))/(2A))-->F
ClrHome
Disp "X="
Disp "X="
Output (1,3,E)
Output (2,3,F)
1-->R
If E=F
0-->R
End
If D<0
Then
ClrHome
(sqrt(-D))-->M
(round(B,2))-->L
(round(M,4))-->M
(2A)-->J
(round(J,3))-->J
If B>=0
Output(1,1,"-")
Output(1,2,L)
Output(1,8,"+-")
Output(1,10,M)
Output(1,16,"I")
Output(2,1,"----------------")
Output(3,6,J)
End
(-B/(2A))-->H
((A(H^2))+(BH)+C)-->K
Output(4,1,"VERTEX")
Output(5,1,"(")
(round(H,3))-->U
(round(K,3))-->V
Output(5,2,U)
Output(5,8,",")
Output(5,9,V)
Output(5,16,")")
If (C-K)=0
Goto 9
(((0-H)^2)/(4(C-K)))-->P
Output(6,1,"P=")
(round(P,7))-->S
Output(6,3,S)
Output(7,1,"FOCUS")
Output(8,1,"(")
Output(8,2,"U")
Output(8,8,",")
Output(6,1,"P=")
(V+P)-->G
Output(8,9,G)
Output(8,16,")")
Lbl 9
Menu("DISPLAY GRAPH?","NO",A,"YES",B)
Lbl A
Stop
Lbl B
Menu("USE","STANDARD GRAPH",C,"AUTO ADJUST",D)
Lbl C
0-->Q
Goto E
Lbl E
prgmRESETSG
If Q=1
Then
(K-P)-->J
If B=0
Then
If C=0
Then
Goto 8
End
End
If A>0
Then
If J<0
(J+(2(J/10)))-->Ymin
If J>0
(J-(2(J/10)))-->Ymin
If R=0
(K+(8(J/10)))-->Ymax
If R=1
(abs (2(J/10)))-->Ymax
End
If A<0
Then
If J<0
(J-(2(J/10)))-->Ymax
IfJ>0
(J+(2(J/10)))-->Ymax
If R=0
(K+((8J)/10))-->Ymin
If R=1
(-abs ((2J)/10))-->Ymin
End
If A>0
Ymax-->N
If A<0
Ymin-->N
((sqrt(abs (4P(N-K))))+H)--Xmax
((-sqrt(abs (4P(N-K))))+H)--Xmin
End
Lbl 8
"K-P"-->Y9
"AX^2+BX+C"-->Y0
DispGraph
Pt-On(H,G)
Trace
FnOff
prgmRESETSG
Output(8,16,"")
Stop
End




----------------------------------------------
Notes
  --sqrt is (2nd x^2)
  --use (x squared button) instead of x^2
  --to get lowercase a,b, and c, use (VARS, 5, EQ)
  -- >=, and <= can be accessed through (2nd, MATH)
  --Requires program RESETSG
  --Ymax, Ymin, Xmax, and Xmin are under (WINDOW)