What is the solution of the system of equations $c+3d=8$ and $c=4 d-6$ ?

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Answer 1 · 2015-03-28T10:30:41

The answer is:

$c=2$
$d=2$ .

Because:

$c+3d=8$
$c=4d-6$

Let's substitue $c$ from the second equation to the first:

$4d-6+3d=8rArr7d=14rArrd=2$

and now let's go back:

$c=4*2-6=2$ .

What is the solution of the system of equations c+3d=8c+3d=8 and c=4 d-6c=4 d-6?