Respuesta :

Answer:

17.32 units

Step-by-step explanation:

The above triangle is a right-angled triangle understood by the small square which denotes the angle there is 90°

Using Pythagoras theorem for right-angled triangle,

b^2+10^2=20^2

or,b^2+100=400

or,b^2=300

or,b=10√3=17.32 units. [ANS]