Respuesta :

Step-by-step explanation:

4x + 8y = 40

4x + (8×0.8) = 40

4x + 6.4 = 40

4x = 33.6

4x÷4 = 33.6 ÷ 4

x = 8.4

Answer:

8.4

Step-by-step explanation:

:D