Why is Rank of matrix [1, -0.8], [-0.8, 0.64] equal to 1?

102 Views Asked by Bumbble Comm At 30 Mar 2026 - 6:29

Why the result is 1? there are two rows/column, that are not equal and can not be made by multiplying from an other.

There are 3 best solutions below

Bumbble Comm On 02 Feb 2017 - 11:21 BEST ANSWER

Hint:

The first column, multiplied by $-0.8$, is...

Bumbble Comm On 02 Feb 2017 - 11:22

The problem is that multiplying the first row by $-0.8$ you obtain the second row.

Bumbble Comm On 02 Feb 2017 - 11:24

Because 2×2 determinant of your matrix is = 0

Therefore rank is $1$