Question

i need help i have a time rates problems here with answers but i don't understand..Please someone explain this to pls.

http://www.mathalino.com/reviewer/differential-calculus/35-36-time-rates-lenghtening-shadow-and-movement-its-tip-3d-space

Answer 1

do we have to reinvent the wheel for this? or is there something in specific that your stuck on?

Answer 2

i really don't understand why is the come up with such equation for the problem

Answer 3

well, lets see what we can deduce

Answer 4

An arc light hangs at the height of 30 ft above the center of a street 60 ft wide.

A man 6 ft tall walks along the sidewalk at the rate of 4 ft/sec. How fast is his shadow lengthening when he is 40 ft up the street?

there are 2 aspects to consider right? how the light and the shadow interact in 3d space

Answer 5

i don't know how to start solving the problem.i'm confused in making the equation.

Answer 6

yes

Answer 7

this is really a 2d problem of similar triangles

Answer 8

the issue being is that it is on an odd plane in space

Answer 9

why is the formula became x=\[\sqrt{(4t)^2+30^2}\]