A) 4y + 2x=10 / * (-2) 3x + 8y=10 -8y - 4x = -20 3x + 8y = 10 --------------------- -x = -10 / * (-1) x = 10 4y + 2x = 10 4y + 2 * 10 = 10 4y + 20= 10 / -20 4y = -10 / : 4 y = -2,5 x = 10 y = -2,5
a) 4y+2x=10 /*(-3) 3x+8y=10 /*2 -6x-12y=-30 6x+16y=20 _______________ 4y=-10 /:4 y=-2i1/2 4*(-5/2)+2x=10 -20/2+2x=10 2x=10+10 /:2 x=10 b) 4a+2b=10 /*5 5a-2b=-10 /*(-4) 20a+10b=50 -20a+8b=40 ____________ 18b=90 /:18 b=5 4a+2*5=10 4a=10-10 a=0 c) 5a+8b=14 /*4 4a+3b=1 /*(-5) 20a+32b=56 -20a-15b=-5 _______________ 17b=51 b=3 5a+8*3=14 5a=14-24 5a=-10 a=-2 d) 4(x-2)-(4-2)=1 10x-2=18 4x-8-4+2=1 10x=18+2 4x=1-2+4+8 10x=20 4x=11 x=11/4 x=2i3/4 10x=20 x=2