Answer:
18cm 
Explanation:
Area of Trapezium = 1/2(a + b) h 
Where: 
A = 352cm^2 
h = distance between parallel sides = 16cm 
a = 25cm
b = ? 
352 = 1/2 (25 + b) 16 
352 = (25 + b) 8 
352 = 200 + 8b 
352 - 200 = 8b 
152 = 8b 
152/8 = b 
19= b 
→b = 19cm 
The other parallel side is 19cm.