Question

What is the length of CD ? In this diagram ABC EDC ? Please help !!!!

Answer 1

Answer:
CD = x = 4 units

Explanation:
We are given that the two triangles are similar. This means that we can set the similarity proportionality as follows:
$\frac{BC}{CD} = \frac{CA}{CE} = \frac{AB}{ED}$

W e have:
BC = 20 - x
AC = 20
CD = x
CE = 5

Substitute in the above proportionality and solve for x as follows:
$\frac{20-x}{x} = \frac{20}{5} = 4$

4x = 20 - x
5x = 20
x = 4

Based on he above:
CD = 4 units
BC = 20 - x = 20 - 4 = 16 units

Hope this helps :)

Answer 2

Answer: 4 (apex)

Step-by-step explanation: