The solution to the system of equations x + 2y = 1 and -3x-2y = 5 is:
x = -3, y = 2
The given system of equations:
x + 2y = 1............(1)
-3x - 2y = 5..........(2)
This can be written in matrix form as shown:
![\left[\begin{array}{ccc}1&2\\-3&-2\end{array}\right] \left[\begin{array}{ccc}x\\y\end{array}\right] = \left[\begin{array}{ccc}1\\5\end{array}\right]](https://tex.z-dn.net/?f=%5Cleft%5B%5Cbegin%7Barray%7D%7Bccc%7D1%262%5C%5C-3%26-2%5Cend%7Barray%7D%5Cright%5D%20%5Cleft%5B%5Cbegin%7Barray%7D%7Bccc%7Dx%5C%5Cy%5Cend%7Barray%7D%5Cright%5D%20%3D%20%5Cleft%5B%5Cbegin%7Barray%7D%7Bccc%7D1%5C%5C5%5Cend%7Barray%7D%5Cright%5D)
Find the determinant of ![\left[\begin{array}{ccc}1&2\\-3&-2\end{array}\right]](https://tex.z-dn.net/?f=%5Cleft%5B%5Cbegin%7Barray%7D%7Bccc%7D1%262%5C%5C-3%26-2%5Cend%7Barray%7D%5Cright%5D)

![\triangle_x = \left[\begin{array}{ccc}1&2\\5&-2\end{array}\right]\\\triangle_x = 1(-2)-2(5)\\\triangle_x = -2-10\\\triangle_x =-12](https://tex.z-dn.net/?f=%5Ctriangle_x%20%3D%20%5Cleft%5B%5Cbegin%7Barray%7D%7Bccc%7D1%262%5C%5C5%26-2%5Cend%7Barray%7D%5Cright%5D%5C%5C%5Ctriangle_x%20%3D%201%28-2%29-2%285%29%5C%5C%5Ctriangle_x%20%3D%20-2-10%5C%5C%5Ctriangle_x%20%3D-12)
![\triangle_y = \left[\begin{array}{ccc}1&1\\-3&5\end{array}\right]\\\triangle_y = 1(5)-1(-3)\\\triangle_y = 5 + 3\\\triangle_y =8](https://tex.z-dn.net/?f=%5Ctriangle_y%20%3D%20%5Cleft%5B%5Cbegin%7Barray%7D%7Bccc%7D1%261%5C%5C-3%265%5Cend%7Barray%7D%5Cright%5D%5C%5C%5Ctriangle_y%20%3D%201%285%29-1%28-3%29%5C%5C%5Ctriangle_y%20%3D%205%20%2B%203%5C%5C%5Ctriangle_y%20%3D8)


The solution to the system of equations x + 2y = 1 and -3x-2y = 5 is:
x = -3, y = 2
Learn more here: brainly.com/question/4428059
Answer:
The width of the building is 50 lamps and 60 lamps will be needed.
Step-by-step explanation:
The perimeter is computed by the sum of the sides of the building, since the length and width are equal on the oposite sides of the building, the perimeter is given by:
perimeter = 2*length + 2*width
900 = 2*(400) + 2*width
2*width + 800 = 900
2*width = 900 - 800
2*width = 100
width = 100/2 = 50 feets
To know how many lights bulbs will be needed we need to take the perimeter of the building and divide it by the space between the lamps. We have:
number o lamps = 900/15 = 60 lamps
Answer:
Amy would have 2.15 left
Step-by-step explanation:
To find out how much she has left, subtract the cost of the items from 10.
10 - 0.75 - 5.50 - 1.60 = 2.15
Answer:
We have that 
Step-by-step explanation:
We have just to replace n=10 on the general equation

Therefore:

Answer:
C. y<3
Step-by-step explanation:
We are required to determine the solution set of the inequality

Step 1: Add 9 to both sides

Step 2: Divide both sides by 15

The solution set of the given inequality is: y<3.
The correct option is C.