Respuesta :
Answer:
-2
Step-by-step explanation:
Between the first two steps we see ...
[tex]15(x-\boxed{^})=25\\\\15x+30=25[/tex]
Applying the distributive property to the first equation and comparing to the second, we see that ...
[tex]-15\boxed{^}=30\\\\\boxed{^}=\dfrac{30}{-15}=-2[/tex]
The number in the box should be -2.