Hello !
Answer:
4x² + 3x + 4
Step-by-step explanation:
(3x² + 2x + 3) + (x² + x + 1)
= 3x² + 2x + 3 + x² + x + 1
= 3x² + x² + 2x + x + 3 + 1
= 4x² + 3x + 4
