1) 2x + 4*(40-x) = 102x + 160 - 4x = 10-2x + 160 = 10-2x = -6x = 30
Ответ: x = 30
2) 4x + 2*(40-x) = 104x + 80 - 2x = 102x + 80 = 102x = 2x = 10
Ответ: x = 10
1) 2x + 4*(40-x) = 10
2x + 160 - 4x = 10
-2x + 160 = 10
-2x = -6
x = 30
Ответ: x = 30
2) 4x + 2*(40-x) = 10
4x + 80 - 2x = 10
2x + 80 = 10
2x = 2
x = 10
Ответ: x = 10