Question

URGENT :)) HELP PLS

(Q2)
The matrix equation represents a system of equations.

A matrix with 2 rows and 2 columns, where row 1 is 2 and 3 and row 2 is 1 and 2, is multiplied by matrix with 2 rows and 1 column, where row 1 is x and row 2 is y, equals a matrix with 2 rows and 1 column, where row 1 is 5 and row 2 is 4.


Solve for x and y using matrices. Show or explain all necessary steps.

Answer 1

The given matrix equation can be written as:

[2 3; 1 2] * [x; y] = [5; 4]

Multiplying the matrices on the left side of the equation gives us the system of equations:

2x + 3y = 5 x + 2y = 4

To solve for x and y using matrices, we can use the inverse matrix method. First, we need to find the inverse of the coefficient matrix [2 3; 1 2]. The inverse of a 2x2 matrix [a b; c d] can be calculated using the formula: (1/(ad-bc)) * [d -b; -c a].

Let’s apply this formula to our coefficient matrix:

The determinant of [2 3; 1 2] is (22) - (31) = 1. Since the determinant is not equal to zero, the inverse of the matrix exists and can be calculated as:

(1/1) * [2 -3; -1 2] = [2 -3; -1 2]

Now we can use this inverse matrix to solve for x and y. Multiplying both sides of our matrix equation by the inverse matrix gives us:

[2 -3; -1 2] * [2x + 3y; x + 2y] = [2 -3; -1 2] * [5; 4]

Solving this equation gives us:

[x; y] = [-7; 6]

So, the solution to the system of equations is x = -7 and y = 6.