Answer:
x = -44/13
y = -65/13
Step-by-step explanation:
Using matrix form means using the crammers rule
The matrix form of the expression is written as;
![\left[\begin{array}{ccc}8&5\\-1&1\\\end{array}\right] \left[\begin{array}{ccc}x\\y\\\end{array}\right] = \left[\begin{array}{ccc}9\\7\\\end{array}\right]](https://tex.z-dn.net/?f=%5Cleft%5B%5Cbegin%7Barray%7D%7Bccc%7D8%265%5C%5C-1%261%5C%5C%5Cend%7Barray%7D%5Cright%5D%20%5Cleft%5B%5Cbegin%7Barray%7D%7Bccc%7Dx%5C%5Cy%5C%5C%5Cend%7Barray%7D%5Cright%5D%20%3D%20%5Cleft%5B%5Cbegin%7Barray%7D%7Bccc%7D9%5C%5C7%5C%5C%5Cend%7Barray%7D%5Cright%5D)
AX = B
taking the determinant of A;
|A| = 8(1) - 5(-1)
|A| = 8 + 5
|A| = 13
After replacing the first row with the column matrix;
![A_x =\left[\begin{array}{ccc}9&5\\7&-1\\\end{array}\right]](https://tex.z-dn.net/?f=A_x%20%3D%5Cleft%5B%5Cbegin%7Barray%7D%7Bccc%7D9%265%5C%5C7%26-1%5C%5C%5Cend%7Barray%7D%5Cright%5D)
|Ax| = 9(-1)-5(7)
||Ax| = -9 - 35
|Ax| = -44
x = |Ax|/|A|
x = -44/13
similarly for y
![A_x =\left[\begin{array}{ccc}8&9\\-1&7\\\end{array}\right]](https://tex.z-dn.net/?f=A_x%20%3D%5Cleft%5B%5Cbegin%7Barray%7D%7Bccc%7D8%269%5C%5C-1%267%5C%5C%5Cend%7Barray%7D%5Cright%5D)
|Ay| = 8(7)+9
|Ay| = 56+9
|Ay| = 65
y = |Ay|/|A|
y = -65/13
<u>Answer-</u>
Set of constraints to model the problem are,

<u>Solution-</u>
Let us assume,
x = the number of lawns weeded by Gwen,
y = the number of dogs walked by Fabio.
Gwen charges $12 each time she weeds a yard and Fabio charges $9 each time he walks a dog,

They need at least $510 to purchase the new gaming station, means they need $510 or more than $510.
An equation for this situation will be,

The number of dog walked by Fabio has scheduled is no more than twice the number of yards Gwen has scheduled to weed, means y must be less than or equal to 2x.
An equation for this situation will be,

Fabio will walk at least 25 dogs, means y must be greater than of equal to 25.
An equation for this situation will be,

First find 7% of 2,500 which is 175, then you add 175 plus 2,500 and you get 2675. So, Mr. Osmund paid $2,675 for his computer! Hope that helps!
Answer: 45 cats
Step-by-step explanation: since you got 30 dogs. 2x15= 30 so to get the number of cats do 3x 15= 45cats
Answer: 281
Step-by-step explanation: