240 : ( X + 3 )- 5 =7                                 16* ( 11 - x : 8 ) = 64

[latex]240:(x+3)-5=7[/latex]   [latex]240:(x+3)=7+5[/latex]   [latex]240:(x+3)=12[/latex]   [latex]\frac{240}{x+3}=\frac{12}{1}[/latex]   [latex]x+3=240:12[/latex]   [latex]x+3=20[/latex]   [latex]x=20-3[/latex]   [latex]x=17[/latex] ________________________________________________ [latex]240:(17+3)-5=7[/latex] (это проверка)   [latex]240:20-5=7[/latex]   [latex]12-5=7[/latex]   [latex]7=7[/latex] ================================================ [latex]16\cdot(11-x:8)=64[/latex]   [latex]11-x:8=64:16[/latex]   [latex]11-x:8=4[/latex]   [latex]-x:8=4-11[/latex]   [latex]-x:8=-7[/latex]   [latex]-\frac{x}{8}=-\frac{7}{1}[/latex]   [latex]x=-7\cdot(-8)[/latex]   [latex]x=56[/latex] ____________________________________________ [latex]16\cdot(11-56:8)=64[/latex]   [latex]16\cdot(11-7)=64[/latex]   [latex]16\cdot4=64[/latex]   [latex]64=64[/latex]