Question

СРОЧНО ПОЖАЛУЙСТА ДВА УПРАЖНЕНИЯ

Answer 1

№14
1) 0,6(4х-12)-0,4(5x-7) = 12/5x-36/5-2x-14/5= 2/5x-22/5= 2/5x- 4 2/5 = 0,4x - 4,4 = 0,4(x-11)
Если x=4 1/6, то
0,4(4 1/6 - 11)= 2/5(25/6-11) = 2/5*(-41/6) = -41/15 = -2 11/15
2) 5 1/7(у-7)-3 3/7(14-у) = 36/7(у-7)-24/7(14-у) = 36/7у-36-48+24/7у = 60/7у- 84 = 12/7у-84 = 12/7(5у-49)
Если у= -0,4,то
12/7(5*(-0,4)-49)= 12/7(-2-49) = 12/7*(-51) = -612/7 = -87 3/7
№15
1) х-(2x-(4x+3))= x-(2x-4x-3)= x-2x+4x+3= 3x+3 = 3(x+1)
2) 8m-(4n-(6m+(3n+5m)))= 8m-(4n-(6m+3n+5m)) = 8m-(4n-(11n+3n)) = 8m-(4n-11m-3n) = 8m-(n-11m) = 8m-n+11m= 19m-n