D is the midpoint of CE . If CD = 5x and CE = 9x + 8, what is CD?

Answer:
CD = 40
Step-by-step explanation:
Since D is the midpoint, the entire length CE is twice the length of CD, so we have ...
2×CD = CE
2×(5x) = 9x +8
x = 8 . . . . . . . . subtract 9x and simplify
Then the length of CD is ...
CD = 5x = 5·8 = 40