Question

How do you solve the system of equations `-x - 8y = - 16` and `6x + 4y = 8`?

Answer 1

`(x,y)-=(0,2)`

Explanation:

`-x-8y=-16`

`6x+4y=8`

If
`a_(11)x+a_(12)y=b_(11)`

`a_(21)x+a_(22)y=b_(22)`

Cramer's rule can be applied

`(x,y)=((b_(11)a_(22)-b_(22)a_(12))/(a_(11)a_(22)-a_(21)a_(12)),(a_(11)b_(22)-a_(22)b_(12))/(a_(11)a_(22)-a_(21)a_(12)))`

Thus, comparing

#x=((-16xx4-8xx(-8)))/((-1xx4-6xx-8))= ((-64+64))/((-4+48))=0/44=0#

`y=((-1xx8-6xx(-16)))/((-1xx4-6xx-8))=((-8+96))/((-4+48))=88/44=2`

`(x,y)-=(0,2)`