3. Решите уравнение: $$\frac{2}{5}$$k – 1.5

Решение:

$$\frac{2}{5}$$k -1.5 = 4.5

$$\frac{2}{5}$$k = 4.5 + 1.5

$$\frac{2}{5}$$k = 6

k = 6 : $$\frac{2}{5}$$

k = 6 * $$\frac{5}{2}$$ = 3 * 5 = 15

Ответ: k = 15