begin comment 2x2 linear system solution; real a11, a12, a21, a22; real b1, b2; real d, d1, d2; real x1, x2; a11 := 1.0; a12 := 2.0; a21 := 3.0; a22 := -4.0; b1 := 1.0; b2 := -1.0; d := a11*a22 - a12*a21; d1 := b1*a22 - a12*b2; d2 := a11*b2 - b1*a21; x1 := d1 / d; x2 := d2 / d; outstring(1,"determinant = "); outreal(1,d); outstring(1,"\nsolution = "); outreal(1,x1); outreal(1,x2); outstring(1,"\n") end