Question

[x-1целых3/4)*2/3=0
(Х-2целых1/4)*4/5=0
12(х-1целых3/10*5/6)=0
9(х-3целых1/2*4/7)=0

Answer 1

1) [x-1целых3/4)*2/3=0

$(x-1\frac{3}{4} )*\frac{2}{3} =0;\\\\(x-\frac{4*1+3}{4} )*\frac{2}{3} =0;\\\\(x-\frac{7}{4} )*\frac{2}{3} =0;\\\\\frac{2}{3}*x-\frac{2}{3} *\frac{7}{4} =0;\\\\\frac{2}{3}x-\frac{14}{12}=0; \\\\\frac{2}{3}x-\frac{7}{6}=0; |*6\\\\6*\frac{2}{3}x-6*\frac{7}{6}=0; \\\\4x-7=0;\\\\4x=7;\\\\x=\frac{7}{4};$

$x=1\frac{3}{4}$   или   $x = 1,75.$

2) (Х-2целых1/4)*4/5=0

$(x-2\frac{1}{4})*\frac{4}{5}=0;\\\\(x-\frac{4*2+1}{4})*\frac{4}{5}=0;\\\\(x-\frac{9}{4})*\frac{4}{5}=0; \\\\\frac{4}{5}*x-\frac{4}{5}*\frac{9}{4}=0;\\\\\frac{4}{5}x-\frac{36}{20}=0; \\\\\frac{4}{5}x-\frac{9}{5}=0; |*5 \\\\5*\frac{4}{5}x-5*\frac{9}{5}=0; \\\\4x-9=0;\\\\4x=9;\\\\x=\frac{9}{4};$

$x=2\frac{1}{4}$   или   $x=2,25.$

3) 12(х-1целых3/10*5/6)=0

$12*(x-1\frac{3}{10} *\frac{5}{6} )=0; |:12\\\\12:12*(x-1\frac{3}{10} *\frac{5}{6} )=0;\\\\x-1\frac{3}{10} *\frac{5}{6} =0;\\\\x-\frac{10*1+3}{10} *\frac{5}{6} =0;\\\\x-\frac{13}{10} *\frac{5}{6} =0;\\\\x-\frac{13}{2} *\frac{1}{6} =0;\\\\x-\frac{13}{12} =0;$

$x=\frac{13}{12}$   или   $x=1\frac{1}{12} .$

4) 9(х-3целых1/2*4/7)=0

$9*(x-3\frac{1}{2}*\frac{4}{7})=0; |:9\\\\9:9*(x-3\frac{1}{2}*\frac{4}{7})=0;\\\\x-3\frac{1}{2}*\frac{4}{7}=0;\\\\x-\frac{2*3+1}{2}*\frac{4}{7}=0;\\\\x-\frac{7}{2}*\frac{4}{7}=0;\\\\x-\frac{4}{2}=0;\\\\x=\frac{4}{2};\\\\x=2 .$