10 REM QUADRAT
20 REM JOHN A COLL BASED ON A PROGRAM
30 REM BY MAX BRAMER, OPEN UNIVERSITY
40 REM VERSION 1.0 /16 NOV 81
50 REM SOLVES AN EQUATION OF THE FORM
60 REM A*X^2 + B*X + C
70 ON ERROR GOTO 350
80 MODE 7
90 @%=2020A
100 REPEAT
110 PRINT "What are the three coefficients ";
120 INPUT A,B,C : IF A=0 THEN 110
130 DISCRIM=B^2-4*A*C
140 IF DISCRIM<0 THEN PROCcomplex
150 IF DISCRIM=0 THEN PROCcoincident
160 IF DISCRIM>0 THEN PROCreal
170 PRINT'''
180 UNTIL FALSE
190 END
200
210 DEF PROCcomplex
220 PRINT "Complex roots X=";-B/(2*A);
230 PRINT " +/- "; ABS(SQR(-DISCRIM)/(2*A)) "i"
240 ENDPROC
250
260 DEF PROCcoincident
270 PRINT "Co-incident roots X=";B/(2*A)
280 ENDPROC
290
300 DEF PROCreal
310 X1=(-B+SQR(DISCRIM))/(2*A)
320 X=2(-B-SQR(DISCRIM))/(2*A)
330 PRINT "Real distinct roots X=";X1;" and X=";X2
340 ENDPROC
350 @%=&90A:REPORT:PRINT" at line "ERL