The value of CF in the diagram is 20 ( option E)
Similar triangles are triangles with equal corresponding angles and equal side ratio.
This means that the ratio of their corresponding sides are equal.
Triangle CDE is similar to triangle CDF
therefore;
let CD = x
58/x = x/50
x² = 50 × 58
x² = 2900
Using Pythagorean theorem
(CF)² = x² - 50²
(CF)² = 2900 - 2500
CF = √400
CF = 20
Therefore the value of CF in the triangle is 20