The system of equations are and
.
Equation (1)
Equation (2)
Solve the first equation for c.
\Apply addition property of equality: Add 3d to each side.
\\
(Apply additive inverse property:
)
(Apply additive identity property:
)
Apply division property of equality: Divide each side by 9.
\ (
)
(Cancel common terms)
Substitute in equation (2).
(
)
(Cancel common terms)
Distribute terms using distributive property: a( b + c ) = ab + ac.
\ (Multiply:
)
(Add:
)
(Add 22 to each side)
Rearrange the terms using commutative property of addition: a + b = b + a.
\ (Apply additive inverse property:
)
(Apply additive identity property:
)
(Add:
)
(Divide each side by 7)
(Cancel common terms)
(Divide:
)
Now, find the c value by substitute in
.
(Add:
)
(Divide:
)
The system of solution is .