Jawabanmu

2014-03-17T22:05:55+07:00
X/sin 60= 6/ sin 30
x/1/2√3 = 6/ 1/2
x/1/2√3=12
x=6√3
2 1 2
2014-03-17T22:08:04+07:00
Cos 60= PQ/PR
1/2 = 6/PR
PR=12

QR =  \sqrt{12^2-6^2} 
      = \sqrt{144-36} 
      = \sqrt{108} 
      =9 \sqrt{3} 
1 1 1