Question

Using the matrix solver on your calculator, find the solution to the system of

equations shown below.

2x - 4y = 4

x - 2y = 8

Answer 1

Answer:

x = 5

y = - 3/2

Step-by-step explanation:

$\left \{ {{2x-4y =4} \atop {x-2y=8}} \right.$

The augmented matrix is :

$\left[\begin{array}{ccc}2&-4&4\\1&-2&8\\\end{array}\right]$

Now; to Row operations

Swap row 2 to row 1

$\left[\begin{array}{ccc}1&-2&8\\\\2&-4&4 \end{array}\right]$

Multiply row 1 with 2 and add to row 2 ;

1(2) = 2

-2(2) = -4

8(2) = 16

2 +2  = 4

4 +(-4) = 0

16+ 4 =20

Now; we have:

$\left[\begin{array}{ccc}1&-2&8\\\\4&0&20 \end{array}\right]$

changing row 2 back to equation form:

4x + 0y = 20

4x = 20

x = 20/4

x = 5

substituting x = 5 in row 1

x - 2y = 8

5 - 2y = 8

-2y = 8 -5

-2y = 3

y = - 3/2