a) { 3(x-½) + 2(y+3)= 3½ { (3x - 1)/3 - (y + 3)/2 = -1|*6 3x-1,5+2y+6=3,5 6x-2-3y-9=-6 3x+2y+4,5=3,5|-4,5 6x-3y-11=-6|+11 3x+2y=-1|*(-2) 6x-3y=5 -6x-4y=2 6x-3y=5 -7y=7|:7 y=-1 3x-1,5-2-6=3,5|-2,5 y=-1 3x=1|:3 y=-1 x=1/3 b) { (x-3)/4 - (y + 5)/2 = -1,5|*8 { (x-3)/2 - (2y-7)/3 = 1 |*6 2x-6-4y-20=-12|+26 3x-9-4y+14=6|-5 2x-4y=14 3x-4y=1|*(-1) 2x-4y=14 -3x+4y=-1 -x=13|*(-1) x=-13 x=-13 -26-6-4y-20=-12 x=-13 -4y-52=-12|+52 x=-13 -4y=40|:(-4) x=-13 y=-10 c) { (2x-5)/2 - (x-6y)/4 = (x+y)/2|*4 { (3x-1)/10 + (2y-5)/5 =(2x+y)/2 |*10 4x-10-x+6y=2x+2y 3x-1-4y-10=10x+5y 3x+6y-10=2y+2x|+10 3x-4y-11=10x+5y|+11 3x+6y=2y+2x+10|-(2x+2y) 3x-4y=10x+5y+11|-(10x-5y) x-2y=10 -7x+y=11|*(2) x-2y=10 -14x+2y=22 -13x=32
1) { 3(x-½) + 2(y+3)= 3½ { (3x - 1)/3 - (y + 3)/2 = -1 /*6 3x-1,5+2y+6=3,5 6x-2-3y-9=-6 3x+2y+4,5=3,5 6x-3y-11=-6 3x+2y=-1 /*(-2) 6x-3y=5 -6x-4y=2 6x-3y=5 ______ y=-1 x=1/3 2) { (x-3)/4 - (y + 5)/2 = -1,5 /*8 { (x-3)/2 - (2y-7)/3 = 1 / *6 2x-6-4y-20=-12 3x-9-4y+14=6 2x-4y=14 3x-4y=1 /*(-1) 2x-4y=14 -3x+4y=-1 _________ x=-13 y=-10 3) { (2x-5)/2 - (x-6y)/4 = (x+y)/2 /*4 { (3x-1)/10 + (2y-5)/5 =(2x+y)/2 /*10 4x-10-x+6y=2x+2y 3x-1-4y-10=10x+5y 3x+6y=2y+2x+10 3x-4y=10x+5y+11 x-2y=10 -7x+y=11 /*2 x-2y=10 -14x+2y=22 ______________ y=-32/13 x=26,6
