Answer:
The area of the rectangle is increasing at a rate of 84 square centimeters per second.
Step-by-step explanation:
The area for a rectangle is given by the formula:

Where <em>w</em> is the width and <em>l</em> is the length.
We are given that the length of the rectangle is increasing at a rate of 6 cm/s and that the width is increasing at a rate of 5 cm/s. In other words, dl/dt = 6 and dw/dt = 5.
First, differentiate the equation with respect to <em>t</em>, where <em>w</em> and <em>l</em> are both functions of <em>t: </em>
![\displaystyle \frac{dA}{dt}=\frac{d}{dt}\left[w\ell]](https://tex.z-dn.net/?f=%5Cdisplaystyle%20%5Cfrac%7BdA%7D%7Bdt%7D%3D%5Cfrac%7Bd%7D%7Bdt%7D%5Cleft%5Bw%5Cell%5D)
By the Product Rule:

Since we know that dl/dt = 6 and that dw/dt = 5:

We want to find the rate at which the area is increasing when the length is 12 cm and the width is 4 cm. Substitute:

The area of the rectangle is increasing at a rate of 84 square centimeters per second.
Answer:
H0 : μd = 0
H1 : μd ≠ 0
Test statistic = 0.6687 ;
Pvalue = 0.7482 ;
Fail to reject H0.
Step-by-step explanation:
H0 : μd = 0
H1 : μd ≠ 0
Given the data:
Before: 15 26 66 115 62 64
After: 16 24 42 80 78 73
Difference = -1 2 24 35 -18 -9
Mean difference, d ; Σd / n
d = Σx / n = ((-1) + 2 + 24 + 35 + (-18) + (-9))
d = Σx / n = 33 / 6 = 5.5
Test statistic = (d / std / sqrt(n))
std = sample standard deviation = 20.146
Test statistic = 5.5 ÷ (20.146/sqrt(6))
Test statistic = 0.6687
The Pvalue :
P(Z < 0.6687) = 0.7482
At α = 0.05
Pvalue > α ; Hence we fail to reject H0
The data does not suggest a significant mean difference in the average number of accidents after information was added to road signs.
Answer:
120%
Convert fraction (ratio) 30 / 25 Answer: 120%
Answer: A. preserves length, angle measures and distance between points
Rigid motions or isometries are any of the three transformations below
- translation (aka shifting)
- rotation
- reflection
Any of those three transformations will keep the figure the same size and shape. That means distances between any two points are kept the same, and angle measures are kept the same as well. Everything is kept the same. The only difference is that the figure is in a different location, is rotated somehow, or it is reflected some way. You can use a series of transformations to undo everything to get the original figure back.
If you wanted to change the size of the figure, then you would apply dilation, which isn't an isometry.