4b² + 8b + 3 = 0
4b² + 2b + 6b + 3 = 0
2b(2b + 1) + 3(2b + 1) = 0
(2b + 3)(2b + 1) = 0
b = -1/2 or b = -3/2
64 is the answer to your question
Answer:
a) the common difference is 20
b) 
c) the common difference is -13
d) 
Step-by-step explanation:
a) what is the common difference of the sequence xn
Looking at the table, we get x_3=16, x_4=36 and x_5= 56
Deterring the common difference by subtracting x_4 from x_3 we get
36-16 =20
So, the common difference is 20
b) what is x_8? what is x_12
The formula used is: 
We know common difference d= 20, we need to find 
Using
we can find 

So, We have 
Now finding 

So, 
Now finding 

So, 
c) what is the common difference of the sequence 
Looking at the table, we get a_7=104, a_8=91 and a_9= 78
Deterring the common difference by subtracting a_7 from a_8 we get
91-104 =-13
So, the common difference is -13
d) what is a_12? what is a_15?
The formula used is: 
We know common difference d= -13, we need to find 
Using
we can find 

So, We have 
Now finding
, put n=12

So, 
Now finding
, put n=15

So, 
3.14*d
3.14*12= 37.68
Rounded to the nearest hundredth would be 37.7
Option C
The ratio for the volumes of two similar cylinders is 8 : 27
<h3><u>
Solution:</u></h3>
Let there are two cylinder of heights "h" and "H"
Also radius to be "r" and "R"

Where π = 3.14 , r is the radius and h is the height
Now the ratio of their heights and radii is 2:3 .i.e

<em><u>Ratio for the volumes of two cylinders</u></em>

Cancelling the common terms, we get

Substituting we get,



Hence, the ratio of volume of two cylinders is 8 : 27