The inequality is .
Apply subtraction property of inequality: Subtract 15 from each side.
\Apply commutative property of addition: a + b = b + a.
\ (Apply additive inverse property:
)
(Apply additive identity property:
)
(Subtract:
)
Apply subtraction property of inequality: Subtract 3b from each side.
\ (Apply additive inverse property:
)
(Apply additive identity property:
)
(Subtract:
)
Apply division property of inequality: Divide each side by 21.
\ (Cancel common terms)
Graph the solution set on a number line.
Note: A dot means that this point is included in the solution set.
The inequality solution set is .