Step-by-step explanation:
the formula for the length of a median based on the 3 side lengths is
m = sqrt(2AB² + 2AC² - BC²)/2
where BC is the side opposite of the indicated vertex.
let's say
A = (2, 7)
B = (-3, 3)
C = (5, 1)
AB² = (2 - -3)² + (7 - 3)² = 5² + 4² = 25 + 16 = 41
AC² = (2 - 5)² + (7 - 1)² = (-3)² + 6² = 9 + 36 = 45
BC² = (-3 - 5)² + (3 - 1)² = (-8)² + 2² = 64 + 4 = 68
m = sqrt(2×41 + 2×45 - 68)/2 = sqrt(82+90-68)/2 =
= sqrt(104)/2 = sqrt(104/4) = sqrt(26) =
= 5.099019514...