Im not good in math and this is my first question, my best guess is D
I will investigate tommorow this problem a little bit more... <3
"He starts both trains at the same time. Train A returns to its starting point every 12 seconds and Train B returns to its starting point every 9 seconds". Basically, what you need to do is find the least common multiple. The least common multiple of 12 and 9 is 36, so the least amount of time, in seconds, that both trains will arrive at the starting points at the same time is 36 seconds.
Answer:

Step-by-step explanation:
we are given the endpoint i.e P and Q of a line segment
we want to figure out the Midpoint of the Line segment
in order to do so we can use Midpoint formula given by

so let

substitute

simplify addition:

simplify division:

hence,
the Midpoint of the line segment is (3,1)
Ummm is this a full question?