Answer:
Remember, a homogeneous system always is consistent. Then we can reason with the rank of the matrix.
If the system Ax=0 has only the trivial solution that's mean that the echelon form of A hasn't free variables, therefore each column of the matrix has a pivot.
Since each column has a pivot then we can form the reduced echelon form of the A, and leave each pivot as 1 and the others components of the column will be zero. This means that the reduced echelon form of A is the identity matrix and so on A is row equivalent to identity matrix.
The answer is simply C.$2.50
Answer:

Step-by-step explanation:
Given the inequality

First, convert mixed numbers to improper fractions:

Now the inequality looks like

Multiply it by 6:

Step-by-step explanation:
the third of 7 consecutive numbers is 12.
so, this looks like
..., ..., 12, ..., ..., ..., ...
that means the numbers have to be
10, 11, 12, 13, 14, 15, 16
the sum is then
16+10 + 15+11 + 14+12 + 13 = 3×26 + 13 = 91
Answer:
Step-by-step explanation:
(1) Yes