Question

solve and check.
2x = 15 + x

Answer 1

You want to get your like terms together. To do that subtract the x to the other side to get: x=15.
Then all you have to do is plug that number back into the equation 2x=15+x
When you do: 2(15)=15+15
30=30
Thus the x-value works for the equation.

Answer 2

oh I see--you subtract x from both sides of the equation?