# How do I use substitution to find the solution of the system of equations c+3d=8 and c=4d-6?

May 19, 2015

equations provided are:
$c + 3 d = 8$ .................$\left(1\right)$
$c = 4 d - 6$ ..........$\left(2\right)$

Substituting equation $\left(2\right)$ in equation $\left(1\right)$
$c + 3 d = \left(4 d - 6\right) + 3 d = 8$
$7 d - 6 = 8$
$7 d = 14$
$d = 2$

Substituting the value of $d$ to find $c$
$c = 4 d - 6 = 4 \times \left(2\right) - 6 = 8 - 6 = 2$

the solution for the equations are $c = 2 , d = 2$