a) 3(x-4)-4(2x-7)=2(x+5) 3x-12-8x+28=2x+10 -5x-2x=10+12-28 -7x=-6 x=6/7 b) 1-0,2x=-0,3x -0,2x+0,3x=-1 0,1x=-1 /*10 x=-10 c) 1,2-1,9x=0,5(x+3)-0,3(x+5) 1,2-1,9x=0,5x+1,5-0,3x-1,5 1,2-1,9x=0,2x -1,9x-0,2x=-1,2 -2,1x=-1,2 x=-1,2/-2,1 x=12/10 : 21/10 x=12/10*10/21 x=12/21 d) 5/6(y-4)-1/3=1/4(y+5)+1/2 5/6y-20/6-1/3=1/4y+5/4+1/2 5/6y-1/4y=5/4+1/2+20/6+1/3 10/12y-3/12y=15/12+6/12+40/12+4/12 7/12y=65/12 / :(7/12) y=65/12*12/7 y=65/7 y=9 2/7
a). 3(x-4)-4(2x-7)=2(x+5) 3x-12-8x+28=2x+10 -5x-2x=10-28+12 -7x= -6 / :(-7) x=6/7 b). 1-0,2x= -0,3x -0,2x+0,3x= -1 0,1x= -1 / : 0,1 x= -10 c). 1,2-1,9x=0,5(x+3)-0,3(x+5) 1,2-1,9x=0,5x+1,5-0,3x-1,5 -1,9x-0,5x+0,3x= -1,2 -2,1x= -1,2 / :(-2,1) x= -1 i 1/5 : (-2 i 1/10) x= -6/5 : (-21/10) x= -6/5 · (-10/21) x= 4/7 d). 5/6(y-4)-1/3 = 1/4(y+5)+1/2 5/6 y -10/3 -1/3=1/4 y+5/4+1/2 5/6 y-1/4 y=5/4+1/2+1/3+10/3 7/12 y=5/4+1/2+11/3 7/12 y=15/12+6/12+44/12 7/12 y=65/12 / : 7/12 y=65/12 · 12/7 y=65/7 y=9 i 2/7
