The Given Perimeter(P) of rectangle is .
Where l=length, w=wedth.
\Apply to subtraction property of equality: Subtract 2w from each side.
\ (Apply additive inverse property:
)
(Apply additive inverse property:
)
Apply to division property of equality: Divide each side by 2.
\ (Cancel common terms)
(Substitute
)
(Multiply:
)
(Subtract:
)
(Divide:
)
Length in.