5. CD has an endpoint at (2, -1) and a midpoint at (8,3). Which measure is closest to the length of CD?
A 20.4 units
B 8.9 units
C 14.4 units
D 11.7 units​

Respuesta :

Answer: C

Step-by-step explanation:

the equation for X is

[tex]\frac{2+x}{2} =\frac{8}{1}[/tex]  use proportion to solve

2 + x = 16

x = 14

(14,y)

The equation for Y is

[tex]\frac{-1+y}{2} =\frac{3}{1}[/tex] use proportion to solve

-1 + y = 6

y = 7

(14,7)

now use the distance formula

(14,7) (2,-1)

which gets you 14.4 or C