Answer:
50M
Step-by-step explanation:
The area of a trapezium = 1/2 x ( a + b) x h
a and b are the parallel sides
h = height
300sqm = 0.5 x (10 + b) x 10
divide both sides by 10
30 = 0.5 x (10 + b)
Divide both sides by 0.5
60 = (10 + b)
b = 60 - 10 = 50
