Question

An aerial camera is suspended from a blimp and positioned at D. The camera needs to cover 125 meters of ground distance. If the camera hangs 10 meters below the blimp and the blimp
attachment is 20 meters in length, at what altitude from D to B should the camera be flown?

Answer 1

The picture isn't quite clear, so i have include a clearer one in the attachment below.

We need to determine the altitude of segment BD. From taking a look at the picture I can conclude that these triangle( s ) formed through the camera's positioning are proportional to one another, but here is the evidence -

( By Vertical Angle's Theorem, $m$

( By Alternate Interior Angle's Theorem, $m< EFD = m$

( Respectively by Alternate Interior Angle's Theorem, $m< FED = m$

Therefore we can conclude that these triangle are similar to one another, and hence we can create a proportionality as such ( with the lengths ) -

$20m / 125m = 10m / x$

And this " x " is the length of segment BD, which we want to determine -

$20 / 125 = 10 / x - ( Cross Multiply ),\\20x = 125( 10 ),\\20x = 1250,\\\\x = 1250 / 20,\\x = 62.5 m$

The altitude with which the camera should be flown is 62.5 meters.

Hope that helps!