Question

The degree of the determinant with 2 rows and 2 columns is 4​

Answer 1

Answer:

the Answer is 4

which you have already given in the question ;)

Answer 2

Answer:

if any determinant A is written as

\begin{gathered}A = \left|\begin{array}{cc}a&b\\c&d\end{array}\right|\end{gathered}

A=

∣

∣

∣

∣

∣

a

c

b

d

∣

∣

∣

∣

∣

then, modulus of A or, value of A is given by

multiply of a and d - multiply of b and d

e.g., |A| = ad - bc

use this concept here,

Given,

\begin{gathered}A= \left|\begin{array}{cc}-1&7\\2&4\end{array}\right|\end{gathered}

A=

∣

∣

∣

∣

∣

−1

2

7

4

∣

∣

∣

∣

∣

|A| = (-1) × 4 - 7 × 2 = -4 - 14 = -18

hence,value of determinant = -18