Solution: (1) According to the meaning of the question: y = (2.3-2) x+(3.5-3) (4500-x) =-0.2x+2250.

(2) According to the meaning of the question: 2x+3(4500-x)≤ 10000.

2x+ 13500-3x≤ 10000

The solution is x≥3500 yuan.

∫k =-0.2 < 0，

∴y decreases with the increase of X.

When x=3500, y=-0.2×3500+2250= 1550.

A: The highest daily profit of this factory 1550 yuan.