Answer:
2y^2+18x
Step-by-step explanation:
4y^2 + 6x -2y^2 + 12x
=4y^2-2y^2+6x+12x
=2y^2+6x+12x
=2y^2+18x
4y^2+6x-2y^2+12x
=4y^2-2y^2 6x+12x