Jawabanmu

2014-03-12T20:34:06+07:00
Jawaban paling cerdas!
2014-03-12T20:35:27+07:00
D²= s²-(R+r)²
20²=29²-(16+r)²
400=841-(16+r)²
(16+r)²= 841-400
16+r= √441
16+r=21
r= 21-16
r= 5
1 5 1