A streetlight post needs some extra support for potential bad weather and high winds. The city wants to install metal support brackets on the light post. Each bracket will be braced into the ground and will then attach to a point on the pole that is 4.5 ft. from the ground. Each bracket is 6.5 ft. long. How far from the base of the pole should each bracket be braced in the ground? Round to the nearest tenth.(1 point) Responses 62.5 ft. 62.5 ft. 22.0 ft. 22.0 ft. 4.7 ft. 4.7 ft. 7.9 ft.

1 answer

To determine how far from the base of the pole each bracket should be braced in the ground, we can use the Pythagorean theorem.

We know:

  • The length of the bracket (hypotenuse) is 6.5 ft.
  • The height at which the bracket is attached to the pole (vertical leg) is 4.5 ft.

We need to find the distance from the base of the pole (horizontal leg). We can denote this distance as \( x \).

According to the Pythagorean theorem:

\[ a^2 + b^2 = c^2 \]

Where:

  • \( a \) is the height of the attachment (4.5 ft),
  • \( b \) is the distance from the base of the pole (x),
  • \( c \) is the length of the bracket (6.5 ft).

Plugging in the values:

\[ (4.5)^2 + x^2 = (6.5)^2 \]

Calculating the squares:

\[ 20.25 + x^2 = 42.25 \]

Now, we can isolate \( x^2 \):

\[ x^2 = 42.25 - 20.25 \] \[ x^2 = 22 \]

Now, take the square root to find \( x \):

\[ x = \sqrt{22} \approx 4.69 \]

Rounding to the nearest tenth, we get:

\[ x \approx 4.7 \]

So the distance from the base of the pole should be approximately 4.7 ft.