Respuesta :

zarampa

Answer:

The number is:

25

Step-by-step explanation:

-3(a-15) = -30

-3*a -3*-15 = -30

-3a + 45 = -30

-3a = -30 - 45

-3a = -75

a = -75/-3

a = +25

a = 25

Check:

-3(25-15) = -30

-3*10 = -30