Determinants and linear equations
Category. determinants
1. Two-row determinant
3. determinant sets:
I. The value of a determinant does not change, if
a) the rows are swapped with the columns,
b) adds the elements of one series multiplied by the same factor to the corresponding elements of a parallel other series.
II. A determinant changes its sign, if you interchange two parallel rows.
III. A determinant has the value zero, if
a) all elements of a series are zero,
b) two parallel rows are equal or proportional.
IV. A determinant is multiplied by a factor, by multiplying all elements of a series by this factor.
B. Two equations with two variables x1 , x2
