Question

A cable 20 feet long connects the top of a flagpole to a point on the ground that is 16 feet from the base of the pole. How tall is the flagpole?(A) 8 ft.(B) 10 ft.(C) 16 ft. (D) 26 ft.

Answer 1

The height of the flagpole is: 12 ft.

Explanation:

Let the height of the flagpole be: x ft.

Now, we can model this problem with the help of a right angled triangle such that the hypotenuse of the triangle is: 20 feet

and one of the leg of the right triangle is: 16 feet

Now, in order to find the other leg i.e. x we need to use the Pythagorean Theorem.

i.e.

`20^2=x^2+16^2\\\\i.e.\\\\400=x^2+256\\\\x^2=400-256\\\\x^2=144\\\\x=\pm 12`

But the height can't be negative.

Hence, we get:

`x=12`