Answer:
The general formula for the total surface area of a regular pyramid is T. S. A. =12pl+B where p represents the perimeter of the base, l the slant height and B the area of the base.
Answer: -258
<u>Step-by-step explanation:</u>
Given the sequence {-8, 16, -32, 64, ... , a₇} we know the following
- the first term (a₁) = -8
- the common ratio (r) = -2
- the number of terms (n) = 7
Input the information above into the Sum formula:
![S_n=\dfrac{a_1(1-r^n)}{1-r}\\\\S_7=\dfrac{-8(1-(-2)^7)}{1-(-2)}\\\\.\quad =\dfrac{-8(1-(-128))}{1+3}\\\\.\quad =\dfrac{-8(129)}{4}\\\\.\quad =-2(129)\\\\.\quad =-258](https://tex.z-dn.net/?f=S_n%3D%5Cdfrac%7Ba_1%281-r%5En%29%7D%7B1-r%7D%5C%5C%5C%5CS_7%3D%5Cdfrac%7B-8%281-%28-2%29%5E7%29%7D%7B1-%28-2%29%7D%5C%5C%5C%5C.%5Cquad%20%3D%5Cdfrac%7B-8%281-%28-128%29%29%7D%7B1%2B3%7D%5C%5C%5C%5C.%5Cquad%20%3D%5Cdfrac%7B-8%28129%29%7D%7B4%7D%5C%5C%5C%5C.%5Cquad%20%3D-2%28129%29%5C%5C%5C%5C.%5Cquad%20%3D-258)
Answer:
$839.95
Step-by-step explanation:
Sales tax = 7 % × cost
Sales tax = 0.07 × 785
Sales tax = $54.95
=====
Cost = price + sales tax
Cost = 785 + 54.95
Cost = $839.95
The cost to purchase is $839.95.
11. As the number 11 there is only extended. If it is wrong, don't come blaming me!!