The equation is .
(Subtract 7x from each side)
(Apply additive inverse property:
)
(Apply commutative property of addition:
)
(Subtract:
)
(Subtract 9 from each side)
(Apply commutative property of addition:
)
(Apply additive inverse property:
)
(Apply additive identity property:
)
(Subtract:
)
(Divide each side by negative 3)
(Cancel common terms)
(Divide:
)
Check:
\To check the solution substitute in the original equation.
(Multiply:
)
(Add:
)
The equality is true.
The solution is .