Answer:
x = - 12
Explanation:
9 - 0.5x = 15
* isolate the variable using inverse operations *
step 1 subtract 9 from each side
9 - 9 cancels out
15 - 9 = 6
now we have -0.5x = 6
step 2 divide each side by -0.5
-0.5x / -0.5 = x
6 / -0.5 = - 12
we're left with x = - 12