a) 0,4x+0,3y=1,4/*(-10) 0,1x+3y=2,3 -4X-3y= -14 0,1x+3y=2.3 -3,9x=-11,7/*10 -39x=117/:39 X=3 0,1*3+3y=2,3 0,3+3y=2,3 3y=2,3-0,3 3y=2/:3 y=2/3 b) 2x+3y=14/*2 3x-2y=8/*3 4x+6y=28 9x-6y=24 13x=52/:13 x=4 3*4-2y=8 12-2y=8 -2y=8-12 -2y=-4/(-2) y=2 c) 3x+4y=1⅔/*3 6x+3y=1¼ /*4 9x+12y=2 24x+12=1/*(-1) 9x+12y=2 -24x-12y=-1 -15x=1/:15 x=1/15 3*1/15+4y=8/3 1/5+4y=8/3 4y=8/3-1/5 4y=40/15-3/15 4y=37/15/:4 y=37/60
a) 0,4x+0,3y=1,4 /*10 0,1x+3y=2,3 4x + 3y = 14 0,1x + 3y = 2,3 3y = 14 - 4x 0,1x + 3(14 - 4x) = 14 3y = 14 - 4x 0,1x + 42 - 12x = 14 3y = 14 - 4x - 11,9x = - 28 3y = 14 - 4x x = 0,425 3y = 14 - 1,7 x = 0,425 3y = 12,3 x = 0,425 y = 4,1 x = 0,425 b) 2x+3y=14 / * 2 3x-2y=8 / * 3 4x + 6y = 28 9x - 6y = 24 13 x = 52 x = 4 16 + 6y = 28 x = 4 6y = 12 x = 4 y = 2 x = 4 c) 3x+4y=1⅔ /*3 6x+3y=1¼ /*4 9x + 12y = 5 24x + 12y = 5 12y = 5 - 12x 24x + 5 - 12x = 5 12y = 5 - 12x 12x = 0 12y = 5 - 0 x = 0 y = 0,4 x = 0