Решите уравнение : 4/9х+1/3х=6,3

4/9 * х + 1/3 * х = 6,3;

4/9 * х + (1 * 3) / (3 * 3) * х = 6,3;

4/9 * х + 3/9 * х = 6,3;

7/9 * х = 6,3;

х = 6,3 : 7/9;

х = 6 3/10 : 7/9;

х = 63/10 : 7/9;

х = 63/10 * 9/7;

х = (63 * 9) / (10 * 7);

х = 567/70;

х = 81/10;

х = 8 1/10.

Проверка:

 4/9 * 8 1/10 + 1/3 * 8 1/10 = 6,3;

 4/9 * 81/10 + 1/3 * 81/10 = 6,3;

(4 * 81) / (9 * 10) + (1 * 81) / (3 * 10) = 6 3/10;

324/90 + 81/30 = 63/10;

324/90 + (81 * 3) / (3 * 30) = 63/10;

324/90 + 243/90 = 63/10;

(324 + 243) / 90 = 63/10;

567/90 = 63/10;

63/10 = 63/10. Решение верно.