Answer:
Step-by-step explanation:
Notice that the series: 1 - 3 + 9 - 27 +... clearly has powers of the factor 3 in its terms and it is also an alternate series (the terms alternate from positive to negative). The terms are positive for 
(even terms) , while the odd terms 
are negative. (so most likely there should be a factor (-1) in the common ratio.
We can then represent it with the following summation expression:
given that each of its first four terms are:
Answer:
2n-8
Step-by-step explanation:
twice n is 2n. decreased by 8 is the -8
We evaluate b^2 - 4ac. If the answer is positive, then there are two real solutions. If it is zero, there is one real solution. If it is negative, there are 2 complex solutions. In this equation, a = 1, b = 5, c = 7. Now we plug in the numbers.
Because this answer is positive, there are two real solutions.
Answer: $18
Step-by-step explanation:
Let x= Pretax price of the meal.
Given: Sales tax = 8%
Tip percent = 20%
As per given ,
Amount spent = ( Pretax price) + (Sales tax ) of (Pretax price) + (Tip percent)of (Pretax price)
= x+ 8% of x + 20% of x
= x +0.08+0.20x
= 1.28x
∵ Amount spent = $23.04
So,
Hence, the pretax price of the meal= $18.
