REVISED ANSWER.
In the picture, I have drawn on the example given. the RC and PD are the same because They are across from each other perfectly. So the answer is still PD=400m but if there can be two answers then I would have to say another possiblity would be 200m for the diameter of the pond. The wording of this problem is tricky and the picture can throw you off a bit but I did my best to answer properly here.
So if you could mark brainliest that would be awesome.
For this case we have that by definition, the equation of a line in the slope-intersection form is given by:
Where:
m: It's the slope
b: It is the cut-off point with the y axis
We have two points that belong to the AB line:
We can find the slope:
By definition, if two lines are parallel then their slopes are equal. Thus, a line parallel to AB will have slope , then the equation will be of the form:
We substitute the given point and find b:
Finally, the equation is:
Answer: