Jawabanmu

2014-05-07T21:52:03+07:00
Caranya ya:
=20²-(7+5)²
=400-12²
=400-144
=√256
=16
Sekian

3 4 3
2014-05-07T21:52:55+07:00
D²=p²-(R+r)²
   =20²-(7+5)²
   =400-144
   =√256
   =16
 
3 3 3