Question

How do you solve the following system: # 8x - y = 13 , 5x-9y=-23 #?

Answer 1

`x=140/67=2 6/67`
`y=249/67 =3 48/67`

Explanation:

System of equations:
1) `8x-y=13 => y=8x-13`
2) `5x-9y=-23 => 9y=5x+23`
1) inserted in 2) gives:
3) `9(8x-13)=5x+23 => 72x-117=5x+23`
`67x=140 => x=140/67=2 6/67`
Inserted in 1):
`y=8*2 6/67-13=16 48/67 - 13=3 48/67`

Check: `5x-9y=5*2 6/67 - 9*3 48/67=-23`