The equation is
(Distributive property: a (b + c) = ab + ac, a (b - c) = ab - ac)
(Multiply:
)
Apply Subtracion property of equality: Subtract 3d from each side .
\ (Commutative property of addition: a + b = b + a)
(Subtract:
)
(Subtract 40 from each side)
(Additive inverse property :
)
(Additive identity property :
)
(Subtract:
)
(Divide each side by 2)
(Cancel common terms)
(Divide:
)
Graph the solution set on a number line
Check:
\To check, substitute a number , in
.
(Substitute:
)
(Add :
)
(Multiply:
)
The equlity is true
The inequality solution is .