#1**+1 **

I will assume for this problem that \(x2\hspace{1mm}\text{means}\hspace{1mm}{x^2}\). In this problem, there is only one like term in the expression \( x^2+2x-1+x^2+6y^9\); the 2 x^2-terms. Let's combine them:

\( x^2+2x-1+x^2+6y^9=2x^2+2x-1+6y^9\)

Normally, I would stop here, but sometimes you should order your terms in term of its individual degree. If this is the case, your final answer is:

\(6y^9+2x^2+2x-1\)

.TheXSquaredFactor Jun 22, 2017