The sum of the length l and the width w of a rectangular region is 210 meters. Write the area A as a function of w.
A) $A ( w ) = w ^ { 2 } - 210 w$
B) $A ( w ) = w ^ { 2 } + 210 w$
C) $A ( w ) = w - 210$
D) $A ( w ) = 210 - w$
E) $A ( w ) = 210 w - w ^ { 2 }$

Question

Quizplus · Accepted Answer

Given $l + w = 210$, we can express $l$ as $l = 210 - w$. The area $A$ of a rectangle is given by $A = l \times w$, substituting $l$ gives $A(w) = (210 - w) \times w = 210w - w^2$.

The Sum of the Length L and the Width W A(w)=w2−210wA ( w ) = w ^ { 2 } - 210 wA(w)=w2−210w

The Sum of the Length L and the Width W $A ( w ) = w ^ { 2 } - 210 w$