15x - 25 - 18x + 9 = 5x - 4-3x - 16 = 5x - 4-3x - 5x = 4 - 16-8x = -12x = -12 / -8x = 1.5
Проверка:5(31.5 - 5) - 3(61.5 - 3) = 5*1.5 - 45(4.5 - 5) - 3(9 - 3) = 7.5 - 45(-0.5) - 3(6) = 3.5-2.5 - 18 = 3.53.5 = 3.5
Решение верно.
15x - 25 - 18x + 9 = 5x - 4
-3x - 16 = 5x - 4
-3x - 5x = 4 - 16
-8x = -12
x = -12 / -8
x = 1.5
Проверка:
5(31.5 - 5) - 3(61.5 - 3) = 5*1.5 - 4
5(4.5 - 5) - 3(9 - 3) = 7.5 - 4
5(-0.5) - 3(6) = 3.5
-2.5 - 18 = 3.5
3.5 = 3.5
Решение верно.