11  REM ::: SOLVE A SYSTEM OF LINEAR EQUATIONS
22  REM ::: A1*X1 + A2*X2 = B1
33  REM ::: A3*X1 + A4*X2 = B2
44  REM --------------------------------------
510 READ A1, A2, A3, A4
615 LET D = A1 * A4 - A3 * A2
720 IF D = 0 THEN 65
830 READ B1, B2
937 LET X1 = (B1*A4 - B2*A2) / D
1042 LET X2 = (A1*B2 - A3*B1) / D
1155 PRINT X1, X2
1260 GOTO 30
1365 PRINT "NO UNIQUE SOLUTION"
1470 DATA 1, 2, 4
1580 DATA 2, -7, 5
1685 DATA 1, 3, 4, -7
1790 END
18