Suppose A is a 5times7 matrix. How many pivot columns must A have if its columns span set of real numbers RSuperscript 5? Why?

Five

Step-by-step explanation:

Pivot columns are said to be columns where pivot exist and a pivot exist in the first nonzero entry of each row in a matrix that is in a shape resulting from a Gaussian elimination.

Suppose A = 5 × 7 matrix

So; if A columns span set of real numbers R⁵

The number of pivot columns that A must have must be present in each row. In a  5 × 7 matrix ; we have 5 rows and 7 columns . So , since A must be present in each row, then :

The matrix must have five pivot columns and we can infer that about  the statements that "A has a pivot position in every row"  and "the columns of A spans R⁵" are logically equivalent.

  y= -3x is the required function.

step-by-step explanation:

we have been given a table:

x             y

0             0

1             -3

3             -9

-2             6

we can see that the values of y is -3 times the value of x

hence, the function would be: y= -3x.

put the values of x will give the same y as in the table that means function is satisfying the given table.

so, converting firstly the mixed fractions to improper fractions and then "adding".