10. a) [latex] frac{a}{2} +2+ frac{a}{2} =3/-2 [/latex] [latex] frac{2a}{2} =1 [/latex] /·2 2a=2 /÷2 a=1 b) [latex] frac{3y}{4} - frac{4}{5}= frac{4}{5}y+ frac{1}{5} -y-1/+ frac{4}{5} [/latex] [latex] frac{3y}{4}= frac{3}{5} y+ frac{1}{5}-1+ frac{4}{5}/- frac{3}{5} y [/latex] [latex] frac{3y}{4} - frac{3}{5}y= frac{5}{5} -1 [/latex] [latex] frac{3y}{4}- frac{3}{5}y=1-1 [/latex] [latex] frac{3y}{4}- frac{3}{5}y=0/*20 [/latex] [latex] 15y-12y=0[/latex] 3y=0/÷3 y=0 c) [latex]- frac{x}3} -0,4= frac{3}{5}- frac{x+1}{2} /+0,4 [/latex] [latex]- frac{x}{3}= frac{3}{5}- frac{x+1}{2}+ frac{2}{5}/ +frac{x+1}{2} [/latex] [latex]- frac{x}{3}+ frac{x+1}{2}= frac{1}{5}/*6 [/latex] -2x+3x+3=[latex] frac{6}{5} [/latex]/-3 x=-[latex] frac{9}{5} [/latex] x=-1,8 d) y+[latex] frac{3(2-y)}{2}=- frac{1}{6}+ frac{-3-y}{3} [/latex] y+[latex] frac{6-3y}{2}=- frac{1}{6} + frac{-3-y}{3}/- frac{-3-y}{3} [/latex] y+[latex] frac{6-3y}{2}- frac{-3-y}{3}=- frac{1}{6} /*6 [/latex] 6y+18-9y+6+2y=1/-24 -y=-23/·(-1) y=23 11. a) [latex] frac{x-1}{2}=4,6+3 frac{1}{2}x/-3 frac{1}{2}x [/latex] [latex] frac{x-1}{2}- frac{7}{2}x=4,6/*2 [/latex] x-1-7x=9,2/+1 -6x=10,2/÷(-6) x=-1,7 b) [latex] frac{7x}{2}+ frac{2x}{3}=11x+13 frac{2}{3}/-11x [/latex] [latex] frac{7x}{2}+ frac{2x}{3}-11x= frac{41}{3}/*6 [/latex] 21x+4x-66x=82 -41x=82/÷(-41) x=-2 c) [latex] frac{2,5x-2}{2}= frac{8x+0,5}{7}/ *14 [/latex] 17,5x-14=16x+1/+14 17,5x=16x+15/-16x 1,5x=15/÷1,5 x=10 d) [latex] frac{x-5}{8}= frac{5x-18}{12}//*24 [/latex] 3x-15=10x-36/-10x -7x-15=-36/+15 -7x=-21/÷(-7) x=3 e) [latex] frac{4}{9}x-2= frac{5}{12}x-1 frac{1}{3}/- frac{5}{12}x [/latex] [latex] frac{4}{9}x-2- frac{5}{12}x=- frac{4}{3}/+2 [/latex] [latex] frac{16}{36}x- frac{15}{36}x=- frac{4}{3}+2 [/latex] [latex] frac{1}{36}x= frac{2}{3}/*36 [/latex] x=24 f) [latex] frac{2x-5}{3}-1=10,2+x/+1 [/latex] [latex] frac{2x-5}{3}=10,2+x+1/-x [/latex] [latex] frac{2x-5}{3}-x=11,2/*3 [/latex] 2x-5-3x=33,6/+5 -x=38,6/·(-1) x=-38,6
