how do I solve thing

There are multiple things we can do with this equation. Letś first find for x.
Given: x+2y=10
Subtraction: x=10-2y
Now that we have x, we can find y!
Given: x+2y=10
Simplify: (10-2y)+2y=10
Now, no matter what we do, the answer will be something called "Infinitely Many." This means, there is not one or two or zero or 5 answers, there is infinite.
Now, let's try finding y without using what we found for x.
Given: x+2y=10
Subraction: 2y=10-x
Division: y=5-x/2
Maybe, now that we have y, we can solve the equation
Given: x+2y=10
Simplify variables:
(10-2y)+(5-x/2)=10
If i'm not mistaken, we can combine the two parenthesis like this: (15-(2y+x/2))=10
Subtract 15: -(2y+x/2)=-5
Swap the negative signs: 2y+x/2=5
Multiply by 2: 2y+x=10
Divide by 2: y+x=5
To me, it looks like we have our answer. We need more information to solve this equation any further, therefore, the answer is clear.
Answer: No Answer / Unsolvable Equation.