Jawabanmu

2014-09-02T10:18:51+07:00
10 + x / 10 = 12/8 
 <kali silang >12 * 10 = (10+x) * 8
120 = 80 + 8x
120-80 = 8x
40 = 8x
40/8 = x
5 = x 
10 + 5 = 15