Answer:
a) the common difference is 20
b) ![x_8=115 , x_{12}=195](https://tex.z-dn.net/?f=x_8%3D115%20%2C%20x_%7B12%7D%3D195)
c) the common difference is -13
d) ![a_{12}=52, a_{15}=13](https://tex.z-dn.net/?f=a_%7B12%7D%3D52%2C%20a_%7B15%7D%3D13)
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: ![x_n=x_1+(n-1)d](https://tex.z-dn.net/?f=x_n%3Dx_1%2B%28n-1%29d)
We know common difference d= 20, we need to find ![x_1](https://tex.z-dn.net/?f=x_1)
Using
we can find ![x_1](https://tex.z-dn.net/?f=x_1)
![x_n=x_1+(n-1)d\\x_3=x_1+(3-1)d\\15=x_1+2(20)\\15=x_1+40\\x_1=15-40\\x_1=-25](https://tex.z-dn.net/?f=x_n%3Dx_1%2B%28n-1%29d%5C%5Cx_3%3Dx_1%2B%283-1%29d%5C%5C15%3Dx_1%2B2%2820%29%5C%5C15%3Dx_1%2B40%5C%5Cx_1%3D15-40%5C%5Cx_1%3D-25)
So, We have ![x_1 = -25](https://tex.z-dn.net/?f=x_1%20%3D%20-25)
Now finding ![x_8](https://tex.z-dn.net/?f=x_8)
![x_n=x_1+(n-1)d\\x_8=x_1+(8-1)d\\x_8=-25+7(20)\\x_8=-25+140\\x_8=115](https://tex.z-dn.net/?f=x_n%3Dx_1%2B%28n-1%29d%5C%5Cx_8%3Dx_1%2B%288-1%29d%5C%5Cx_8%3D-25%2B7%2820%29%5C%5Cx_8%3D-25%2B140%5C%5Cx_8%3D115)
So, ![\mathbf{x_8=115}](https://tex.z-dn.net/?f=%5Cmathbf%7Bx_8%3D115%7D)
Now finding ![x_{12}](https://tex.z-dn.net/?f=x_%7B12%7D)
![x_n=x_1+(n-1)d\\x_{12}=x_1+(12-1)d\\x_{12}=-25+11(20)\\x_{12}=-25+220\\x_{12}=195](https://tex.z-dn.net/?f=x_n%3Dx_1%2B%28n-1%29d%5C%5Cx_%7B12%7D%3Dx_1%2B%2812-1%29d%5C%5Cx_%7B12%7D%3D-25%2B11%2820%29%5C%5Cx_%7B12%7D%3D-25%2B220%5C%5Cx_%7B12%7D%3D195)
So, ![\mathbf{x_{12}=195}](https://tex.z-dn.net/?f=%5Cmathbf%7Bx_%7B12%7D%3D195%7D)
c) what is the common difference of the sequence ![a_m](https://tex.z-dn.net/?f=a_m)
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: ![a_n=a_1+(n-1)d](https://tex.z-dn.net/?f=a_n%3Da_1%2B%28n-1%29d)
We know common difference d= -13, we need to find ![a_1](https://tex.z-dn.net/?f=a_1)
Using
we can find ![x_1](https://tex.z-dn.net/?f=x_1)
![a_n=a_1+(n-1)d\\a_7=a_1+(7-1)d\\104=a_1+7(-13)\\104=a_1-91\\a_1=104+91\\a_1=195](https://tex.z-dn.net/?f=a_n%3Da_1%2B%28n-1%29d%5C%5Ca_7%3Da_1%2B%287-1%29d%5C%5C104%3Da_1%2B7%28-13%29%5C%5C104%3Da_1-91%5C%5Ca_1%3D104%2B91%5C%5Ca_1%3D195)
So, We have ![a_1 = 195](https://tex.z-dn.net/?f=a_1%20%3D%20195)
Now finding
, put n=12
![a_n=a_1+(n-1)d\\a_{12}=a_1+(12-1)d\\a_{12}=195+11(-13)\\a_{12}=195-143\\a_{12}=52](https://tex.z-dn.net/?f=a_n%3Da_1%2B%28n-1%29d%5C%5Ca_%7B12%7D%3Da_1%2B%2812-1%29d%5C%5Ca_%7B12%7D%3D195%2B11%28-13%29%5C%5Ca_%7B12%7D%3D195-143%5C%5Ca_%7B12%7D%3D52)
So, ![\mathbf{a_{12}=52}](https://tex.z-dn.net/?f=%5Cmathbf%7Ba_%7B12%7D%3D52%7D)
Now finding
, put n=15
![a_n=a_1+(n-1)d\\a_{15}=a_1+(15-1)d\\a_{15}=195+14(-13)\\a_{15}=195-182\\a_{15}=13](https://tex.z-dn.net/?f=a_n%3Da_1%2B%28n-1%29d%5C%5Ca_%7B15%7D%3Da_1%2B%2815-1%29d%5C%5Ca_%7B15%7D%3D195%2B14%28-13%29%5C%5Ca_%7B15%7D%3D195-182%5C%5Ca_%7B15%7D%3D13)
So, ![\mathbf{a_{15}=13}](https://tex.z-dn.net/?f=%5Cmathbf%7Ba_%7B15%7D%3D13%7D)
Answer:
you do Length x Width x height
8 3/8 x 6 x 8 1/4 = 414.56
hope this helps :-)
Ignore the top pat of the picture that’s my government homework. The answer is 104ft.
Answer:
X is equal
Step-by-step explanation:
look at the angle
Answer:
−2=−2x^3
Step-by-step explanation:
10x3= 3x2−20x−6=(10x3⋅(3x2))(−20x−6)=−600x6−180x5x2=−600x6−180x5−2x⋅(2x2)=−4x3−2x⋅x2=−2x^3
−2=−2x3
2x^2=−2x^3
−2=−2x^3