Answer:
a) 9
b) -3
Step-by-step explanation:
a)
|9+x|=2x
9 + x = 2x
- x -x
---------------
9 = x
b)
|x+6|=2x+9
x +6 = 2x +9
-x -x
6 = x + 9
-9 -9
--------------
-3 = x
