Solution: (1) Let the width of the tongue be xcm and the length of the box bottom be ycm. ..

According to the meaning of the question, x+4y=26.

2x+4.5y=3 1

The solution is x=2.

y=6

6×2.5= 15 (cm)

Answer: The width of the tongue is 2cm, and the height of the paper box is 15cm. ..

(2)8cm。