Answer:
-20
Explanation:
The first thing you want to do is inverse operation (In this scenario you have negative 75 but change it to positive 75 and add that +75 to +25)
25=-75-5x
+75 +75
__________
100 = -5x
Now divide 100 by negative 5
100 = -5x
________
-5 -5
Which you should get -20
-20 = x