Answer:
a)-3
b)2
c)27
you subtract 9 from both sides
-12x+9-9=-15-9
simplify=-12x=-15x-9
add 15x to both sides=-12x+15x=-15x-9+15x
Simplify=3x=-9
divide both sides by 3
3x/3=-9/3
x=-3
b)Step 1: Subtract 8.5x from both sides.
4.5x+11.5−8.5x=8.5x+3.5−8.5x
−4x+11.5=3.5
Step 2: Subtract 11.5 from both sides.
−4x+11.5−11.5=3.5−11.5
−4x=−8
Step 3: Divide both sides by -4.
−4x/−4=−8/−4
x=2
Answer: x=2
Step 1: Subtract 1/3x from both sides.
2/3x−9=1/3x
2/3x-9-1/3x=1/3x-1/3x
1/3-9=0
Step 2: Add 9 to both sides.
1/3x-9+9=0+9
1/3x=9
Step 3: Multiply both sides by 3.
3*(1/3x)=(3)*(9)
x=27
hope that was useful would appreciate a brainliest if it helps you