Answer: 14 a hour
Step-by-step explanation:
Answer:
Step-by-step explanation:
ignore the "at the instant the man is 30 feet away" part, set it as X and the man's shadow as Y.
Similar triangles so we can do
.
Solve for it we get 44y = 6x
Differentiate relative to time t, we get 44y' = 6x'.
change in x (x') is equal to 5. And we get the answer y' =
.
the
ft/sec is the rate of which the length of the shadow is changing. add 5 to it for the rate of the tip of his shadow moving away from the tower.
9514 1404 393
Answer:
Step-by-step explanation:
These "special" right triangles have side length ratios that it is useful to remember.
<u>45°-45°-90° triangle</u>
Sides have the ratios 1 : 1 : √2. That is, x is √2 times as long as the side length shown as 18.
x = 18√2
<u>30°-60°-90° triangle</u>
Shortest to longest, sides have the ratios ...
1 : √3 : 2
That is, y is √3 times the length of the side marked 18, and z is 2 times the length of the side marked 18.
y = 18√3
z = 2·18 = 36