The equation is .
According to subtraction property of equality: Subtract from each side.
(Apply commutative property of of addition:
)
(Apply additive inverse property:
)
(Apply additive identity property:
)
(Subtrct:
)
According to subtraction property of equality: Subtract 9 from each side.
\ (Apply additive inverse property:
)
(Apply additive identity property:
)
(Subtract:
)
Check:
\To check the solution, substitute in original equation.
(Multiply:
)
(Add:
)
Compare the values, the equation is true.
The value of .