Answer:
They will need √161 feet, or about 12.69 feet of fencing. √161 is irrational because 161 is not a perfect square.
Step-by-step explanation:
[tex] {8}^{2} + {x}^{2} = {15}^{2} [/tex]
[tex]64 + {x}^{2} = 225[/tex]
[tex] {x}^{2} = 161[/tex]
[tex]x = \sqrt{161} = 12.69[/tex]
