Answers

2016-06-28T20:04:51+08:00
Yung pangatlong number na nasa bilog, yun yung third arithmetic mean. :)
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thank you i love u ate Savior ka
haha :)
2016-06-28T20:23:49+08:00
M=a+b/2
m=-9+9/2
m=0/2
m=0

Therefore, 0 is the third term

further formulation 
an=a1+(n-1)d
a7=a1+(7-1)d
9=-9+6d
9+9=6d
18=6d
18/6=6d/6
3=d

a1=-9
a2=-6
a3=-3
a4=0
a5=3
a6=6
a7=9


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