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

Mar 28, 2015

$c = 2$
$d = 2$.

Because:

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

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

$4 d - 6 + 3 d = 8 \Rightarrow 7 d = 14 \Rightarrow d = 2$

and now let's go back:

$c = 4 \cdot 2 - 6 = 2$.