first determine whether arithmetic sequence or geometric
both seem to be arithmetic
first one
adds 9
starts with -7
an=a1+(n-1)d
a1=first term
d=common difference
an=-7+9(n-1)
51 term is
a51=-7+9(51-1)
a51=-7+9(50)
a51=-7+450
a51=443
51term is 443
adds 6 every times
starts with -9
an=-9+6(n-1)
22nd term
a22=-9+6(22-1)
a22=-9+126
a22=117
22nt term is 117
