Both Coordinates should be negative
You haven't provided the steps.
mathisfun.com/geometry/construct-linebisect.html
Here is a useful link to the correct steps. The instructions may not be exactly the same but I think you can do it.
Answer:
18
Step-by-step explanation:
Area of <span>parallelogram
A = bh
so
b = A/h
b = </span><span>216.24 / 15.9
</span>b = 13.6
answer
<span>base of the parallelogram = 13.9 cm</span>