15 * ( а + 2 ) = 6 * (2а + 7 )
15а + 30 = 12а + 42
15а - 12а = 42 - 30
3а = 12
а =12 : 3
а = 4
12b - 7 * (b + 4 ) = 26 - 4b
12b -7b -28 = 26 - 4b
12b -7b + 4b = 26 + 28
9b = 54
b = 54 : 9
b = 6
5 * (3c + 2) = 8 * (9 -2c)
15c + 10 = 72 -16c
15c + 16c = 72 - 10
31c = 62
c = 62 : 31
c = 2
10k +2 * (7k - 2 ) = 5 * (4k + 3 ) + 3k
10k + 14k - 4 = 20k + 15 + 3k
10k + 14k -20k -3k = 15 + 4
k = 19
Если треугольник равносторонний то 100:3=3,33
p=a+a+a
1)723-319=404
6*404=2424
2430-2424=6
6×2=12
12+488=500
2)1500-1496=4
4×5=20
2×11=22
20+22=42
1428÷42=34
34-34=0
3)512+548=1060
7×216=1512
2×324=648
1512-1060=452
452+648=1100
1100÷11=100
48:
48, 24, 16, 12, 8, 6, 4, 3, 2, 1
75:
75, 25, 5, 1