A trapezoid has two parallel sides
and two not parallel sides.
If we draw another line inside the trapezoid
half way between the top and bottom lines.
This line will cut the sides on the left and right
exactly in half.
Now try this ...
Draw a line inside the trapezoid
one third of the way down from the top line
to the bottom line.
Because 1/3 is EXACTLY half as big as 2/3.
Since the side on the left
and the side on the right are not parallel,
one can be really long and the other can be really short.
In any case, the lengths on the left
will usually not be the same as the lengths on the right.
By the way I'm 9.