A ladder 39 ft long leans against a vertical wall. If the lower end is being moved away from the wall at the rate of 4 ​ft/sec, how fast is the height of the top changing​ (this will be a negative​ rate) when the lower end is 15 feet from the​ wall?

Answers

Answer 1
Answer:

Answer:

-5/3 ft/sec

Step-by-step explanation:

In this question, we are asked to calculate the rate at which the height of the top of a ladder is changing given that the lower end is being dragged at a particular rate.

Please check attachment for complete solution and step by step explanation.

Answer 2
Answer:

Answer:

The rate of change of height,  dy / dt = -1.667 ft/s  

Step-by-step explanation:

Solution:-

- The length of the ladder, L = 39 ft

- The foot of the ladder is moved away from wall at a rate, dx/dt = 4ft/s

Find:-

how fast is the height of the top changing​ (this will be a negative​ rate) when the lower end is 15 feet from the​ wall?

Solution:-

- We will first draw a right angle triangle, with vertical height of the ladder to be"y" and distance of the foot of the ladder and the wall to be "x".

- Then express the length "L" in terms of x and y using pythagorean theorem:

                        L^2 = x^2 + y^2

                        y^2 = 39^2 - x^2  

- Taking height of the ladder as the dependent variable and distance of the foot of the ladder from wall as independent variable.

- Formulate a differential equation from the given expression above in terms of "dy/dt" and "dx/dt". Perform implicit differential of the computed expression "d/dt":

                        2y*dy/dt = -2x*dx/dt

                        dy / dt = -(x/y)*dx/dt

- Where, dy / dt : The change in height of the ladder.

- The height of the ladder at x = 15 ft is:

               y =  √(39^2 - x^2) = √(39^2 - 15^2) = 36

- Then evaluate dy/dt:

                        dy / dt = -(15/36)*4

                        dy / dt = -1.667 ft/s      

                       


Related Questions

How old do you have to be in order to be in a relationship?no reason at all.....
The product of twenty-one negative integers is negative. TRUE or FALSE.
For the values a = 2.9 which is a leg of a right triangle, and value c = 4.2, which is the hypotenuse, find the length of the other leg, b, to the nearest tenth.A. 2.9 B. 3.0 C. 2.8 D. 1.3
12323. Short Answer--- Emily slid down Shethe sliding board at the park. A. topWhere did Emily have the most bottpotential energy? B. Where didEmily have the most kineticenergy?.I need help with this plz
If an equation of the linear function in the figure above is y=mx=b, than m=

What is a line graph

Answers

A graph in which points representing values of a variable for suitable values of an independent variable are connected by a broken line.


Example attached!

A line chart or line graph is a type of chart which displays information as a series of data points called 'markers' connected by straight line segments.

Round 1330.464489 to one decimal place

Answers

Answer:

1330.5

Step-by-step explanation:

I rounded to the tenths place.

Answer:

1330.5

Step-by-step explanation:

Hope this helps! <3

The fourth-grade students at Harvest School make up 0.3 of all students at the school. What fraction is equivalent to 0.3?

Answers

The three is in the tenths place so the numerator is 3 and the denominater is 10 so the equivalent fraction would be 3/10

What is the domain and range of the following relations/functions?

Answers

step by step:

the domain of a function is the values of x it can be

the range is the values of y it can be

domain:

1 \leqslant x < 4

range:

3 \leqslant y < - 3

Find f (3) of the function: x square - 2x + 1​

Answers

Answer:

f(3) = 4

Step-by-step explanation:

To evaluate f(3) substitute x = 3 into f(x) , that is

f(3) = 3² - 2(3) + 1 = 9 - 6 + 1 = 4

There are about 2.2 pounds in one kilogram. If Miguel's bag weighs37.4 kilograms, about how many pounds does it weigh? Did you multiply

or divide to find your answer? my last points help ASAP

Answers

Answer:

82.28

Step-by-step explanation:

1kg=2.2 pounds

37.4 * 2.2 = 82.28