First, You Do 10 and 12 in the parentheses, then subtract 8 and multiply 7. Then This Equals 146. Hope this helps :)
Answer: The Answer IS Either Letter B Or Letter C
B.
an=100 · (12)n−1a subscript n baseline equals 100 times left parenthesis one half right parenthesis superscript n minus 1 baseline
Step-by-step explanation: I Think The Answer IS Letter B
Simplify the matrix.
a
=
100
,
a
n
=
12
a
n
−
a
,
1
,
100
,
n
,
−
h
a
l
f
,
n
,
1
...............................................................................................................................................
So, you already know that angle CBD is 68 degrees, and the complementary angle to angle CBD is angle CBA. These angles together make 180 degrees because segment DBA is a straight line consisting of angles CBD and CBA. 180-68(the angle you already know) is 112 degrees for angle CBA. Then you repeat this process to find the other angles
6a-2(a-1)
6a-2a-2
4a-2
I think it is 4a-2