Nora is creating a dog run for her dog, Mr. Darcey. She has enough fencing material for a fence with a perimeter of 120 feet. This situation is modeled using the equation A=−w2+60w

𝐴
=

𝑤
2
+
60
𝑤
where A
𝐴
is the area and w is the width. Using this equation, identify the maximum range or area the fence can have.(1 point)
square feet

1 answer

To find the maximum area that the fence can enclose, we can analyze the quadratic equation given:

\[ A = -w^2 + 60w \]

This is in the standard form of a quadratic equation \( A = ax^2 + bx + c \) where \( a = -1 \), \( b = 60 \), and \( c = 0 \).

The maximum value of a quadratic function occurs at the vertex, which for the equation \( w = -\frac{b}{2a} \).

  1. Calculate \( w \):

\[ w = -\frac{60}{2(-1)} = \frac{60}{2} = 30 \]

  1. Now, substitute \( w = 30 \) back into the area equation to find the maximum area:

\[ A = -30^2 + 60(30) \] \[ A = -900 + 1800 \] \[ A = 900 \]

Thus, the maximum area that Nora can enclose with the fence is \( \boxed{900} \) square feet.