Answer: at twice the father's rate of speed. At this rate; how many miles would the bicycle rider travel in 9 hours?
Step-by-step explanation:
at twice the father's rate of speed. At this rate; how many miles would the bicycle rider travel in 9 hours?
Answer:
x = 3
Step-by-step explanation:
1. 5x = 11 +4 (when the negative is moved, it turns positive)
2. 5x = 15
3. divide 15 by 5 and then you get your answer
Answer:
![\left[\begin{array}{cc}2&8\\5&1\end{array}\right]](https://tex.z-dn.net/?f=%5Cleft%5B%5Cbegin%7Barray%7D%7Bcc%7D2%268%5C%5C5%261%5Cend%7Barray%7D%5Cright%5D)
Step-by-step explanation:
The <em>transpose of a matrix </em>
is one where you swap the column and row index for every entry of some original matrix
. Let's go through our first matrix row by row and swap the indices to construct this new matrix. Note that entries with the same index for row and column will stay fixed. Here I'll use the notation
and
to refer to the entry in the i-th row and the j-th column of the matrices
and
respectively:

Constructing the matrix
from those entries gives us
![P^T=\left[\begin{array}{cc}2&8\\5&1\end{array}\right]](https://tex.z-dn.net/?f=P%5ET%3D%5Cleft%5B%5Cbegin%7Barray%7D%7Bcc%7D2%268%5C%5C5%261%5Cend%7Barray%7D%5Cright%5D)
which is option a. from the list.
Another interesting quality of the transpose is that we can geometrically represent it as a reflection over the line traced out by all of the entries where the row and column index are equal. In this example, reflecting over the line traced from 2 to 1 gives us our transpose. For another example of this, see the attached image!
answer
$962.50
set up equation
first, we want to find out how many gallons of gas she'll save a year
x1 = gallons for old car
x2 = gallons for new car
gallons saved = x1 - x2 since she uses more gallons with the old car with a lower miles per gallon
then, find how much she saves on gas by multiply the price per gallon (3.85) by gallons saved
price saved = gallons saved * price
price saved = (x1 - x2) * 3.85
gallons with old car
to find the number of gallons, we divide the number of miles (15000) by miles per gallon (24 for the old car)
x1 = 15000 / 24
x1 = 625
gallons with new car
use the same process as with the old car, but with 40 miles per gallon instead
x2 = 15000 / 40
x2 = 375
plug in values
price saved = (x1 - x2) * 3.85
price saved = (625 - 375) * 3.85
price saved = 250 * 3.85
price saved = $962.50