x+11+x-1

x + x = - 11 + 1

2x = -10
x = -5

or, as written, x+11+x-1 = 2x+10

x+11+x -1

Maybe you are just supposed to simplify because I do not see an = sign
2x +10

To simplify the expression x+11+x-1, we can combine like terms. Like terms are the terms that have the same variable raised to the same power.

So, let's start by combining the x terms. We have x+x, which is equal to 2x.

Next, we combine the constants. We have 11-1, which is equal to 10.

Therefore, the simplified expression is 2x + 10.