The flag polls shadow is 18 feet long. a 3 foot dog is sitting next to the poll. if the dog shadow is 8.1 feet

Question

long, how tall is the flag poll?
PLEASE tell me how to show my work and the answer! i have had soo much trouble with this and my teacher refuses to help.

Answer 1

Well, first you should draw a diagram of the flag pole and the dog.

Assuming the sun hits the dogs and pole at the same angle, you have similar triangles by ~AA (angle-angle) since the angle of the sun to the object is the same, and they are both perpendicular to the ground (creating a right angle ).

Then set up a proportion of height to length for the pole and the dog (let x be the height of the pole):
x/18 feet = 3 feet/8.1 feet

Therefore x, the height of the pole should be (3/8.1)(18) = 6.7feet

Answer 2

Set up a ratio. Ratio of flag pole height to its shadow length is equal to the ratio of the dog height to its shadow length.

Flag pole height = x
Flag pole shadow length = 18
Dog height = 3
Dog shadow length = 8.1

x / 18 = 3 / 8.1

Cross-multiply: 8.1x = 54

Divide by 8.1: x = 6 2/3 = 6.667 feet

Answer 3

oooh okay so you say that the dog is 3 feet and its shadow is 8.1 ft then you have to figure out how long the shadow is for each foot of the object. so thats 8.1 divided by 3 and that comes out to 2.7 feet of shadow per 1 foot of object. then you divide the flagpole shadow by 2.7 to get the amount of feet so 18 divided by 2.7 is... 6.66666666666666667 ft tall so that comes out to 6 2/3 ft tall flag pole or (six and two-thirds)

i hope i did that right!

Answer 4

(x/18) = (3/(8.1))
8.1x = 54
x = 6.67 feet

The pole is 6 feet and 8 inches

Answer 5

18/3
x/8.1
cross multiply
145.8/3x
x=48.6
the flag pole is 48.6

now check it 48.6/18=2.7
8.1/3=2.7