A flagpole casts a shadow 3.5 meters long. Anita is standing near the pole. Her shadow is 0.75 meters long. Anita's height is 1.5 meters. How tall is the flagpole?

3 Answers
Apr 13, 2018

7 metres

Explanation:

0.75 : 1.5 = 3.5 : z (z = flagpole height).

1.5/2 = 0.75. Therefore z/2 = 3.5.

Rearrange this so 3.5 xx 2 = z

z = 7

Apr 13, 2018

The flagpole is 7m high.

Explanation:

The heights and the shadows are in the same ratio because the sun is shining from the same angle, so the triangles formed are similar.

Notice that Anita's height is twice as long as her shadow, so the height of the flagpole will be 2xx3.5 = 7m

We can also write a direct proportion:

x/3.5 = 1.5/0.75" "(larr"heights")/(larr"shadows")

x = (3.5xx1.5)/0.75

x = 7m

Apr 13, 2018

Height of flagpole=7m

Explanation:

:.tan theta=1.5/0.75= ( Opposite)/(Adjacent)=2

:.theta=63^@26'5.8''

the angles of the shadows are the same

:.Opposite=flagpole
:.Adjacent=length of shadow

:.(Opposite)/(Adjacent)=tan theta=tan63^@26'5.8''

:.(Opposite)/(3.5)=2

flagpole=2xx3.5

:.=7m