Question

What is |Ax| in the system below?

Answer 1

Answer:

$c) \left|\begin{array}{ccc}-3&-1\\5&1\\\end{array}\right|$

Step-by-step explanation:

Given system of equations are  

                                                      4 x - y = -3

                                                      -2 x +y = 5

Now the Matrix form AX = B

                            $\left[\begin{array}{ccc}4&-1\\-2&1\\\end{array}\right]$$\left[\begin{array}{ccc}x\\y\\\end{array}\right] = \left[\begin{array}{ccc}-3\\5\\\end{array}\right]$

Now replacing first column with 'B' matrix

                     $|A_{x} | = \left[\begin{array}{ccc}-3&-1\\5&1\\\end{array}\right]$

Now replacing second column with 'B' matrix

                    $|A_{y} | = \left[\begin{array}{ccc}4&-3\\-2&5\\\end{array}\right]$