Answer:
ax+b
Step-by-step explanation:
9514 1404 393
3x^2
Add coefficients of like terms.
(x^2 +2x -1) +(2x^2 -2x +1)
= (1 +2)x^2 +(2 -2)x +(-1 +1)
= 3x^2 +0x +0
= 3x^2