Answer:
3 + x
Step-by-step explanation:
Sum means to add, so you would just add 3 and x (since they haven't given an actual number and only a variable).
This is an equation, you can't write equations as decimals. I think you're asking for x (as a decimal)?
Add 8 to each side: 4+8= 8+(-8)+3x
12=3x
x=4
This is a whole number so it's already in decimal form
