Chapter 7.4, Problem 14E

To determine

To write: the augmented matrixof the given system of linear equation and its dimension.

Answer to Problem 14E

Augmented matrix of the system of equation is

  $\left[\begin{array}{cccc}7& 4& ⋮& 22\\ 5& -9& ⋮& 15\end{array}\right]$

The augmented matrix of the given system of linear equation has dimension $2\times 3$ .

Explanation of Solution

Given information:

A system of linear equation is given as

  $\{\begin{array}{l}7x+4y=22\\ 5x-9y=15\end{array}$

Concept used:

Co-efficient matrix of a system of linear equation of the form $\{\begin{array}{l}{a}_{1}x+b_{1}y=c_1\\ a_{2}x+b_{2}y=c_2\end{array}$ is given by

  $\left[\begin{array}{cc}{a}_1& b_1\\ a_2& b_2\end{array}\right]$

The augmented matrix of the system of linear equation is given by

  $\left[\begin{array}{cccc}{a}_1& b_1& ⋮& c_1\\ a_2& b_2& ⋮& c_2\end{array}\right]$

Dimension of a matrix is

  $\text{Dimension}=\text{Number}\text{of}\text{rows}\times \text{Number}\text{of}\text{columns}$

Consider the given system of equation.

  $\{\begin{array}{l}7x+4y=22\\ 5x-9y=15\end{array}$

Now, the augmented matrix is given by

  $\left[\begin{array}{cccc}7& 4& ⋮& 22\\ 5& -9& ⋮& 15\end{array}\right]$

Here, the number of row of the matrix is 2 and number of columns is 3.

So, dimension of the matrix is

  $\begin{array}{c}\text{Dimension}=\text{Number}\text{of}\text{rows}\times \text{Number}\text{of}\text{columns}\\ =2\times 3\end{array}$

The augmented matrix of the given system of linear equation has dimension $2\times 3$ .