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

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Answer 1 · 2016-03-18T04:10:44

$m=2$
$n=-3$

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.

How do you solve 6m+n=96m+n=9 and m-8n=26m-8n=26 using substitution?