A 5.5-foot-tall woman walks at 8 ft/s toward a street light that is 22 ft above the ground. What is the rate of change of the length of her shadow when she is 20 ft from the street light? At what rate is the tip of her shadow moving?

Step-by-step explanation:

Given

length of shadow =22 ft

height of woman =5.5 ft

speed of woman

from the figure, we can write

at given instant

y=20 ft

so, using similar triangle properties

Again we can write

find the magnitude of the trig term  

csc

(

x

)

−

1

by taking the absolute value of the coefficient.

1

find the lower bound of the range.

tap for more

y

=

−

2

find the upper bound of the range.

tap for more

y

=

0

the range is  

y

≤

−

2

or  

y

≥

0

.

(

−

∞

,

−

2

]

∪

[

0

,

∞

)

{

y

|

y

≤

−

2

,

y

≥

0

}

step-by-step explanation:

answer:   28.56 feet (approx)

step-by-step explanation:

since, triangle abc has measure of angle c equal to 55 degrees, measure of angle abc equal to 90 degrees, and length of bc equal to 20 feet.

we have to find out the measurement of segment ab.

therefore, tan 55° =

but bc = 20 feet.

⇒ tan 55 ° =  

⇒ ab = 20 × tan 55 °

⇒ ab = 20 × 1.42814800674

⇒ ab = 28.5629601348   ≈ 28.56 feet