Answer:
x = 6 m
Step-by-step explanation:
The area (A) of a trapezium is calculated as
A = [tex]\frac{1}{2}[/tex] h (a + b)
where h is the perpendicular height and a, b the parallel bases
Here A = 60, h = 8, a = 9 and b = x , thus
[tex]\frac{1}{2}[/tex] × 8 × (9 + x) = 60, that is
4(9 + x) = 60 ( divide both sides by 4 )
9 + x = 15 ( subtract 9 from both sides )
x = 6 m