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:
[tex] \frac{BC}{CD} = \frac{CA}{CE} = \frac{AB}{ED} [/tex]
W e have:
BC = 20 - x
AC = 20
CD = x
CE = 5
Substitute in the above proportionality and solve for x as follows:
[tex] \frac{20-x}{x} = \frac{20}{5} = 4[/tex]
4x = 20 - x
5x = 20
x = 4
Based on he above:
CD = 4 units
BC = 20 - x = 20 - 4 = 16 units
Hope this helps :)