28.y + 15,81 = 134,81
=> 28.y = 134,81 - 15,81
=> 28.y = 119
=> y = 119 : 28
=> y = 119/28
18*y + 15,81 = 134,81
18*y = 134,81 - 15,81
18*y = 119
y = 119 : 18
y = 119/18
18*y + 15,81 = 134,81
18*y = 134,81 - 15,81
18*y = 119
y = 119 : 18
y = 119/18
28 x y + 15,81 = 134,81
28 x y = 134,81 - 15,81
28 x y = 119
y = 119 : 28
y = 119/28
28 * y +15,81 =134,81
28 * y =134,81 - 15,81
28 * y =119
y =119 : 28
x=119/1 8
chúc bạn học giỏi tk mình nhé
