Question

Michele wanted to measure the height of her school’s flagpole. She placed a mirror on the ground 48 feet from the flagpole, then walked backwards until she was able to see the top of the pole in the mirror. Her eyes were 5 feet above the ground and she was 12 feet from the mirror. Using similar triangles, find the height of the flagpole to the nearest tenth of a foot. Find the geometric mean of the pair of numbers.
A. 20 ft
B. 38.4 ft
C. 55 ft
D. 25 ft


I think D.

Answer 1

The simple proportion for your similar triangles:
h/48 = 5/12
12h = 240
h = 20

or by straight logic:
The mirror is 4 times the distance away from the pole as she is from the mirror.
So the flage pole is 4 times her height, or 20 ft

" Find the geometric mean of the pair of numbers"

Which pair of numbers ?

Answer 2

I've done this before :)

H/48 = 5/12
Cross multiply
12h = 240
H = 240/12
H = 20

I hope this help whoever is reading this answer :)

Answer 3

h=20 so it is A