Answer:
It's very simple!
Explanation:
It's my last answer of the day, so you are lucky!
So, based on the diagram, the two sides are equally balanced(have the same weight), so you can put them equal to each other!
3x+1=x+7
So, if you don't know how to solve it, follow ahead! If you do, here's the answer! x=3 balls <---Answer
So first, you subtract x from both sides!
Then, you subtract one from both sides of the equation!
Then you divide by two on each side!
So, there's the answer!
Hope this helps!
Stay Safe!