Respuesta :

Answer:

x = 22cm

Step-by-step explanation:

Pythagoras Therom a^2 + b^2= C^2

Opposite the right angle is x at the bottom which is the hypotenuse. you only need to work out the bottom triangle so forget the top.

18/2=9 for the bottom length.

9^2 + 20^2 = 481^2 (opposite of squaring)

square root 481 = 21.9317121 rounded up would be 22cm x= 22cm