Answer:
x = 1/2
Explanation:
To solve this, we want x on just 1 side.
We can add x to both sides, to get 10x+15=20 (so we have moved the x across).
Lets now move the numbers onto just one side (we can do this by -15 from both sides).
Consequently, 10x=5
To find x on its own, we can do 5/10, therefore x=1/2