Answer:
Width of rectangular pen = 10 feet
Length of rectangular pen = 20 feet
Step-by-step explanation:
We are given the following in the question:
Area of rectangular dog pen = 300 square feet
Let [tex]x\text{ feet}[/tex] be the width of the rectangular pen.
Then, length of the pen is given by:
[tex]l= (x+10)\text{ feet}[/tex]
Area of rectangular pen = Area of rectangle
[tex]A = l\times w[/tex]
Putting values, we get
[tex]200 = (x+10)x\\200 = x^2 + 10x\\x^2 + 10x-200 = 0\\ (x + 20)(x - 10) = 0\\x = -20, x = 10[/tex]
Since, dimensions can never be negative, we get
Width of rectangular pen = 10 feet
Length of rectangular pen = 20 feet
