Answer:
10 nickels and 10 quarters
Step-by-step explanation:
Given
Number of coins: 20
Vaiue of coins = $3.00
Required
Number of Nickels and Quarters;
<em>Let N =Nickels and Q =Quarters</em>
The total coins is represented as:

1 nickel is equivalent to $0.05 and 1 quarter is equivalent to $0.25; So

Make N the subject of formula in the first equation

Substitute this in the second equation


Collect like terms


Multiply both sides by 5


Recall that N = 20 - Q


Step-by-step explanation:
$75 30% 0.70(75) = x $52.50
$18 65% 0.35(18) = x $6.30
$60 30% 0.70x = 42 $42
$35 20% 0.80x = 28 $28
$150 25% 0.75(150) = x $112.50
Website A:
c = 10 + 0.25 s
where c is the cost and s is the number of songs.
Website B:
c = 0.75 s
The equation ( answer ):
10 + 0.25 s = 0.75 s
We can solve this equation:
10 = 0.5 s
s = 10 : 0.5
s = 20 ( Marvin would have to buy 20 songs to to make the costs equal )
The second matrix
represents the triangle dilated by a scale factor of 3.
Step-by-step explanation:
Step 1:
To calculate the scale factor for any dilation, we divide the coordinates after dilation by the same coordinated before dilation.
The coordinates of a vertice are represented in the column of the matrix. Since there are three vertices, there are 2 rows with 3 columns. The order of the matrices is 2 × 3.
Step 2:
If we form a matrix with the vertices (-2,0), (1,5), and (4,-8), we get
![\left[\begin{array}{ccc}-2&1&4\\0&5&-8\end{array}\right]](https://tex.z-dn.net/?f=%5Cleft%5B%5Cbegin%7Barray%7D%7Bccc%7D-2%261%264%5C%5C0%265%26-8%5Cend%7Barray%7D%5Cright%5D)
The scale factor is 3, so if we multiply the above matrix with 3 throughout, we will get the matrix that represents the vertices of the triangle after dilation.
Step 3:
The matrix that represents the triangle after dilation is given by
![3\left[\begin{array}{ccc}-2&1&4\\0&5&-8\end{array}\right] = \left[\begin{array}{ccc}3(-2)&3(1)&3(4)\\3(0)&3(5)&3(-8)\end{array}\right] = \left[\begin{array}{ccc}-6&3&12\\0&15&-24\end{array}\right]](https://tex.z-dn.net/?f=3%5Cleft%5B%5Cbegin%7Barray%7D%7Bccc%7D-2%261%264%5C%5C0%265%26-8%5Cend%7Barray%7D%5Cright%5D%20%3D%20%5Cleft%5B%5Cbegin%7Barray%7D%7Bccc%7D3%28-2%29%263%281%29%263%284%29%5C%5C3%280%29%263%285%29%263%28-8%29%5Cend%7Barray%7D%5Cright%5D%20%3D%20%5Cleft%5B%5Cbegin%7Barray%7D%7Bccc%7D-6%263%2612%5C%5C0%2615%26-24%5Cend%7Barray%7D%5Cright%5D)
This is the second option.
44 boots were sold all together. To figure this out first you need to find how many of the other boots there were. 8 rugby boots and 12 hiking boots. 8 + 12 + 24 = 44.