1/2, 1/4, 3/4, 1/10, 1/5, 3/5
Дробью 188/15 или 12 целых 8/15
10+3 3/16-2 5/24= 10+51/16-53/24=10+51*3/48-53*2/48=10 47/48
{12 - 2x + 3y = 20
{12 + 4x - 2y = 20
{x = - 4 + 3/2y
{x = 12 + 4x - 2y = 20
12 + 4(- 4 + 3/2y) - 2y = 20
y = 6
12 + 4x - 2 • 6 = 20
x = 5
(x, y) = (5, 6)
{12 - 2 • 5 + 3 • 6 = 20
{12 + 4 • 5 - 2 • 6 = 20
{20 = 20
{20 = 20
(x, y) = (5, 6)
Ответ: х = 5., у = 6.