Question

How do you solve `6m+n=9` and `m-8n=26` using substitution?

Answer 1

`m=2`
`n=-3`

Explanation:

From the given equations
`6m+n=9` first equation
`m-8n=26`second equation

Start with second equation
`m=26+8n`
insert the equivalent in the first equation

`6m+n=9` first equation
`6(26+8n)+n=9` first equation
`156+48n+n=9`
`49n=9-156`
`49n=-147`
`n=-147/49`
`n=-3`

Solve for m now using `n=-3` and `m=26+8n`

`m=26+8n`
`m=26+8(-3)`
`m=26-24`
`m=2`

check:using the original equations
`6m+n=9` first equation
`6(2)+(-3)=9` first equation

`12-3=9`
`9=9`

`m-8n=26`second equation
`2-8(-3)=26`second equation
`2+24=26`
`26=26`

God bless....I hope the explanation is useful.