# Dimensions of a pen????

• Oct 21st 2007, 12:04 PM
Dunit0001
Dimensions of a pen????
A farmer plans to use 25m of fencing to enclose a rectangular pen that has area 63 m^2. Only three sides of the pen need fencing because part of an existing wall will be used for one of the longer sides. Find the dimensions of the pen.
• Oct 21st 2007, 12:11 PM
Jhevon
Quote:

Originally Posted by Dunit0001
A farmer plans to use 25m of fencing to enclose a rectangular pen that has area 63 m^2. Only three sides of the pen need fencing because part of an existing wall will be used for one of the longer sides. Find the dimensions of the pen.

Let the other long side be of length $x$
Let the other two short sides be of length $y$ each

We want $A = xy = 63$

and $x + 2y = 25$

can you take it from here?
• Oct 21st 2007, 12:24 PM
Dunit0001
I got y=9
• Oct 21st 2007, 12:34 PM
Jhevon
Quote:

Originally Posted by Dunit0001
I got y=9

there are two solutions for y, were there not? you should have two sets of solutions since you get a quadratic. y = 9 is one solution for y