Jawabanmu

2014-06-01T09:24:09+07:00
U3 = a+2b
u5 + u7 = a + 4b + a + 6b
36 = a+2b
144 = 2a + 10b
72 = a + 5b
eliminasi
a +    5b = 72
a     + 2b  = 36

3b = 36
b =12 
a = 12

u100 = a + 99b
= 12 + 99(12)
= 12 + 1188
= 1200