Answer:
A
Step-by-step explanation:
(4,1)
solution:
coefficient of determination = R^2 = .85 correlation coefficient, R = 0.92
Answer:
C.
Step-by-step explanation:
Given
![A =(x_1,y_1)](https://tex.z-dn.net/?f=A%20%3D%28x_1%2Cy_1%29)
![B =(x_2,y_2)](https://tex.z-dn.net/?f=B%20%3D%28x_2%2Cy_2%29)
![C =(x_3,y_3)](https://tex.z-dn.net/?f=C%20%3D%28x_3%2Cy_3%29)
![D =(x_4,y_4)](https://tex.z-dn.net/?f=D%20%3D%28x_4%2Cy_4%29)
Required:
Which condition proves that AB is perpendicular to CD
First, calculate the slopes of both.
<u>For AB</u>
![m_1 = \frac{y_2 -y_1}{x_2 - x_1}](https://tex.z-dn.net/?f=m_1%20%3D%20%5Cfrac%7By_2%20-y_1%7D%7Bx_2%20-%20x_1%7D)
<u>For CD</u>
![m_2 = \frac{y_4 -y_3}{x_4 - x_2}](https://tex.z-dn.net/?f=m_2%20%3D%20%5Cfrac%7By_4%20-y_3%7D%7Bx_4%20-%20x_2%7D)
The condition of perpendicularity is:
![m_1 * m_2 = -1](https://tex.z-dn.net/?f=m_1%20%2A%20m_2%20%3D%20-1)
Substitute values for m1 and m2
![\frac{y_2 -y_1}{x_2 - x_1} * \frac{y_4 -y_3}{x_4 - x_2} = -1](https://tex.z-dn.net/?f=%5Cfrac%7By_2%20-y_1%7D%7Bx_2%20-%20x_1%7D%20%2A%20%5Cfrac%7By_4%20-y_3%7D%7Bx_4%20-%20x_2%7D%20%3D%20-1)
Option (c) is correct
80 W divided by 1000 (to convert to kW) = 0.08 kW
The total cost can be calculated by multiplying wattage by time by electricity cost. Note how the units will cancel out, given that 2 weeks is equal to 14 days.
(0.08 kW)(0.5 h/day)(14 days) = 0.56 kWh
Multiply by the cost: ($0.08/kWh)(0.56 kWh) = $0.0448
So the closest answer is the first choice.
The answer/I hope this helps