The length of AB in the diagram is 30
Similar shapes are shapes with thesame type of figure and thesame side ratios.
Triangle EDC is similar to triangle ADB
This means that their side ratio will be equal.
For two triangles to be similar , their corresponding angles must be equal and the ratio of their corresponding sides must be equal.
let AB be x
therefore
x/12 = 10/4
4x = 120
divide both sides by 4
x = 120/4
x = 30
Therefore, the value of x 30