Are for triangle fomula is lengthxwidth and what ever u get is divided by two.
What question? what are you trying to ask?
Answer:

Step-by-step explanation:
The midpoint of two points is the average of the x coordinates and the average of the y coordinates.
Given
A(3, -1)
and we let the other end point B be B(x,y)
and midpoint is (-7,10)
So, the average of 3 and x is -7, and
the average of -1 and y is 10
We can solve for x first:

and now solving for y:

So, the other point B is:

Answer:
Each person runs 3 miles in a relay race.
Step-by-step explanation:
Given:
Distance of Relay race m = 12 miles.
The expression m divided by 4 is the distance each person runs in a relay race that is m miles.
Each person runs in relay race = 
Now given the total distance of the relay race is 12 miles.
i.e. value of m = 12 miles
Now substituting the value of m in above equation we get;
Each person runs in relay race = 
Hence each person runs 3 miles in a relay race.