A because if you use T3 it wouldn’t have make sense so only reasonable and solution that works is A
Answer:
A)
Step-by-step explanation:
check that the formula in A works . . .
the 7th term should be 320
a(320) = 5(2)^7-1
= 5(2)^6
= 5(64)
= 320
Answer:
The answer is
or
.
Step-by-step explanation:
Solve the following equation:

-Multiply
and
to get

So, now you have found the answer.
Answer:
B.
Step-by-step explanation:
Because if you subtract 19x and 18 from each side it wont be 0=0, in other equatins there is infinity solutions