Respuesta :

Answer:

20

Step-by-step explanation:

Since we have given that

Dimensions of a triangle he has to use for fencing are

15 feet, 8 feet, and 20 feet.

1) For making it a right triangle it must satisfy the "Pythagoras theorem" which states that

[tex]H^{2} = B^{2} + P^{2}[/tex]

[tex]20^{2} = 15 + 8^{2}[/tex]

[tex]400 \neq 225 + 64[/tex]

[tex]400 \neq 289[/tex]

No, it will not be able to make a right triangle.

2) Joel cut the longest piece of wood in order to make a right triangle.

So, from above we get that

[tex]\sqrt{} 289 = 17 feet[/tex]

So, the longest side must be 17 feet.

It takes him 30 seconds to install each foot of fencing,

The total perimeter of fencing will be

17 + 15 + 8 = 40 feet

So, for 1 foot he needs = 30 seconds

For 40 feet, he will need

40 × 30 = 1,200 seconds

1200/600 = 20 minutes

Hence, he needs 20 minutes to install all of the fences.