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:
C
Step-by-step explanation:
Answer: 47.1/15
Step-by-step explanation:
We define Circumference by C= pie X D[diameter]
Hence pie= C/ D= 47.1/15
Answers and Step-by-step explanations:
9-18.
a) All the angles of a triangle add up to 180, by definition. So, we can write the expression: 30 + 115 + x = 180.
Then, we can just solve for x by subtracting 30 and 115 from both sides:
x = 180 - 115 - 30 = 35 degrees
b) Again all three angles should add up to 180, so:
x + x + x = 180 ⇒ 3x = 180 ⇒ x = 180/3 = 60 degrees
9-19.
a) These angles add up to 180:
2x + x + 30 = 180 ⇒ 3x + 30 = 180 ⇒ 3x = 150 ⇒ x = 50
2x = 50 * 2 = 100
The missing angles are 100 degrees and 50 degrees.
b) Again, these add up to 180:
x + 10 + x + 90 = 180 ⇒ 2x + 100 = 180 ⇒ 2x = 80 ⇒ x = 40
x + 10 = 40 + 10 = 50
The missing angles are 50 degrees and 40 degrees.
Hope this helps!
