Question

Which determinants can be used to solve for x and y in the system of linear equations below?

Answer 1

Answer:

The right answer is the first answer

Step-by-step explanation:

Look to the attached file

Answer 2

Answer:

The correct answer option is A. $|A|=\begin{vmatrix}-3 &2 \\ 4&-15 \end{vmatrix}\\\\\\|A_{x}|=\begin{vmatrix}-9 &2 \\ -25 &-15 \end{vmatrix}\\\\\\|A_{y}|=\begin{vmatrix}-3 &-9 \\ 4 &-25\end{vmatrix}$.

Step-by-step explanation:

We are given the following system of linear equations:

$-3x+2y=-9$

$4x-15y=-25$

We can create a matrix  AX = b where A is a 2×2 matrix created by the coefficients of x and y and b is a 2×1 matrix formed by the term after equality.

So the correct answer option is:

$|A|=\begin{vmatrix}-3 &2 \\ 4&-15 \end{vmatrix}\\\\\\|A_{x}|=\begin{vmatrix}-9 &2 \\ -25 &-15 \end{vmatrix}\\\\\\|A_{y}|=\begin{vmatrix}-3 &-9 \\ 4 &-25\end{vmatrix}$