Answer:
= 4n - 13
Step-by-step explanation:
There is a common difference d between consecutive terms , that is
d = - 5 - (- 9) = - 1 - (- 5) = 3 - 1 = 7 - 3 = 4
This indicates the sequence is arithmetic with n th term
= a₁ + (n - 1)d
where a₁ is the first term and d the common difference
Here a₁ = - 9 and d = 4, thus
= - 9 + 4(n - 1) = - 9 + 4n - 4 = 4n - 13
<span>According the information given we understand that the room is a regular rectangle, We know that volume = lenght * widht * height, so we start by calculate the room area as length by width, that is 16.4 * 4.5 = 73.8 square metres. Then with 3.26 metres of height, the total volum will 73.8 * 3.26 = 240.58 cubic metres.</span>
Answer:
Area = 12
Step-by-step explanation:
Given
See attachment
Required
Area of 
From the attached image, we have:



The area is then calculated as:

So, we have:

Using a calculator:

Remove absolute bracket


2400 + 100x = 2200 + 120x
2400 - 2200 = 120x - 100x
200 = 20x
200/20 = x
10 = x <== they would have to sell 10 systems