The equation is
.
(Subtract:
)
(Subtract 6 from each side)
(Apply additive inverse property:
)
(Apply additive identity property:
)
(Subtract:
)
(Multiply each side by negative one)
(Product of two same signs is positive)

Check:
\To check the solution, substitute
in original equation.

(Add:
)
The equality is true.
The value of
.