7 = (7·8)/8 = 56/8 7 и 5/8 = 56/8 и 5/8
9 = (9·4)/4 = 36/4 9 и 1/4 = 36/4 и 1/4
4 = (4·7)/7 = 28/7 3/7 и 4 = 3/7 и 28/7
8 = (8·10)/10 = 80/10 9/10 и 8 = 9/10 и 80/10
15 = (15·10)/10 = 150/10 15 и 3/10 = 150/10 и 3/10
20 = (20·8)/8 = 160/8 20 и 3/8 = 160/8 и 3/8
9 = (9·12)/12 = 108/12 9 и 5/12 = 108/12 и 5/12
3 = (3·11)/11 = 33/11 7/11 и 3 = 7/11 и 33/11
Б)-8(k-3)+4(k-2)-2(3k+1)=-8k+24+4k-8-6k-2=-10k+14
В)6+4a-5a+a-7a=6-7a
Г)5(p-2)-6(p+3)-3(2p-9)=5p-10-6p-18-6p+27=-7p-1
Уравнения:
А)0,6(y-3)-0,5(y-1)=1,5
0,6y-1,8-0,5y+0,5=1,5
0,1y=1,8-0,5+1,5
0,1y=2,8
y=28
Б)0,8(x-2)-0,7(x-1)=2,7
0,8x-1,6-0,7x+0,7=2,7
0,1x=1,6-0,7+2,7
0,1x=3,6
x=36