Question

I NEED HELP PLEASE, THANKS! :)

Answer 1

Take a look at the attachment below. It proves that the inverse of matrix P does exists, as option c,

Hope that helps!

Answer 2

Answer:  C

Step-by-step explanation:

Given    a    b

             c    d

Multiply the reciprocal of the determinant by    d   -b

                                                                             -c     a

Determinant = ad - bc = 2(-3) - 4(1)

                                    = -6    -    4

                                    =      -10

$-\dfrac{1}{10}\left[\begin{array}{cc}-3&-4\\-1&2\end{array}\right] \\\\\\\\=\left[\begin{array}{cc}\dfrac{-3}{-10}&\dfrac{-4}{-10}\\\\\dfrac{-1}{-10}&\dfrac{2}{-10}\end{array}\right]\\\\\\\\=\left[\begin{array}{cc}\dfrac{3}{10}&\dfrac{2}{5}\\\\\dfrac{1}{10}&-\dfrac{1}{5}\end{array}\right]$