18) SQUARE ROOT (425 B)
To use: LOAD 7, RUN

10 REM
20 REM SQUARE ROOT
30 REM
40 PRINT "INPUT NUMBER"
50 INPUT A
60 CLS
70 PRINT "SQUARE ROOT OF ";A;" IS"
80 LET U=174
90 LET L=0
100 LET F=0
110 LET D=0
120 LET N=(U+L)/2
130 IF (N-1)**2<A AND (N+1)**2>A THEN GOTO 170
140 IF N**2>A THEN LET U=N
150 IF N**2<A THEN LET L=N
160 GOTO 120
170 IF N**2>A THEN LET N=N-1
180 LET E=100*(A-N**2)
190 IF E<2 THEN GOTO 350
200 LET F=(E/N)/2
210 LET Q=F**2
220 LET E=E-2*N*F
230 IF E>0 THEN GOTO 270
240 LET F=F-1
250 LET E=100*(A-N**2)
260 GOTO 210
270 LET E=10*E-Q/10
280 IF E<0 THEN GOTO 240
290 LET D=(E/N)/2
300 LET H=E-(2*F*D)/2
310 IF H>0 THEN GOTO 340
320 LET D=D-1
330 GOTO 300
340 LET D=(H/N)/2
350 PRINT N;".";F;D
360 STOP