The system of equations are
and
.
Equation (1)
Equation (2)
Solve the second equation for c.
\Apply subtraction property of equality: Subtract 6d from each side.
\\

(Apply additive inverse property:
)
(Apply additive identity property:
)
Apply division property of equality: Divide each side by 6.
\\
\

(Cancel common terms)
Substitute
in
.

Distribute terms using distributive property: a( b
c ) = ab
ac.

(Multiply:
)
(Subtract:
)
(Subtract 36 from each side)
Rearrange the terms using commutative property of addition: a + b = b + a.
\
(Apply additive inverse property:
)
(Apply additive identity property:
)
(Subtract:
)
Apply division property of equality: Divide each side by 5.
\
(Cancel common terms)
Now, find the c value by substituting
in
.

(Product of two same signs is positve)
(Add:
)
The system of solution is
.