(i) Use the formula for the determinant of a 2×2 matrix.


(ii) The adjugate matrix is the transpose of the cofactor matrix of A. (These days, the "adjoint" of a matrix X is more commonly used to refer to the conjugate transpose of X, which is not the same.)
The cofactor of the (i, j)-th entry of A is the determinant of the matrix you get after deleting the i-th row and j-th column of A, multiplied by
. If C is the cofactor matrix of A, then

Then the adjugate of A is the transpose of C,

(iii) The inverse of A is equal to 1/det(A) times the adjugate:

(iv) The system of equations translates to the matrix equation

Multiplying both sides on the left by the inverse of A gives




Answer:
c) does not make sense, y-int is (0,-8). a) the graph does show a linear line. b) sure it works, the x-int is 3. d) yes the line is infinite both ways (x,y) x (infinite, -infinite) y (infinite, - infinite)
Step-by-step explanation:
I hope this helps