A street light is mounted at the top of a 15-ft-tall pole. A man 6 feet tall walks away from the pole with a speed of 5 ft/s along a straight path. How fast (in ft/s) is the tip of his shadow moving when he is 45 feet from the pole
Answers
Answer:
25/3 ft/s
Step-by-step explanation:
Height of pole , h=15 ft
Height of man, h'=6 ft
Let BD=x
BE=y
DE=BE-BD=y-x
All right triangles are similar
When two triangles are similar then the ratio of their corresponding sides are equal.
Therefore,
[tex]\frac{AB}{CD}=\frac{BE}{DE}[/tex]
[tex]\frac{15}{6}=\frac{y}{y-x}[/tex]
[tex]\frac{5}{2}=\frac{y}{y-x}[/tex]
[tex]5y-5x=2y[/tex]
[tex]5y-2y=5x[/tex]
[tex]3y=5x[/tex]
[tex]y=\frac{5}{3}x[/tex]
Differentiate w.r.t t
[tex]\frac{dy}{dt}=\frac{5}{3}\frac{dx}{dt}[/tex]
We have dx/dt=5ft/s
Using the value
[tex]\frac{dy}{dt}=\frac{5}{3}(5)=\frac{25}{3}ft/s[/tex]
Hence, the tip of his shadow moving with a speed 25/3 ft/s when he is 45 feet from the pole.
Answer:
The tip pf the shadow is moving with speed 25/3 ft/s.
Step-by-step explanation:
height of pole = 15 ft
height of man = 6 ft
x = 45 ft
According to the diagram, dx/dt = 5 ft/s.
Now
[tex]\frac{y-x}{y}=\frac{6}{15}\\\\15 y - 15 x = 6 y \\\\y = \frac{5}{3} x\\\\\frac{dy}{dt} = \frac{5}{3}\frac{dx}{dt}\\\\\frac{dy}{dt}=\frac{5}{3}\times 5 =\frac{25}{3} ft/s[/tex]
Related Questions
Plz help me find side x on the triangle
Answers
Answer:
x=71
Step-by-step explanation:
Since this is an isosceles triangle as indicated by the lines on the sides, the sides lengths are equal.
When the sides are equal, the base angles are equal
x=71
prove ||a+b|| ≤ ||a||+|b||
Answers
Step-by-step explanation:
|a+b|=✓(a²+b²)
|a|+|b|=a+b
||a+b|| ≤ ||a||+|b||
Draw the image of the rotation of quadrilateral SORT by 270° about the origin.
I need visual help, not a number answer please :)
Answers
9514 1404 393
Answer:
see attached
Step-by-step explanation:
A rotation 270° CCW is the same as a rotation 90° CW. To see what the figure looks like in its new location, make a copy on a semi-transparent medium, then align the +x axis on the copy with the -y axis on the original graph, keeping the origin in the same place.*
Algebraically, the transformation is ...
(x, y) ⇒ (y, -x)
For example, ...
S(7, -6) ⇒ S'(-6, -7)
In the attachment, the rotated figure is in red.
_____
* The exercise of physically doing this on paper or with transparencies can give you the insight you need to learn to do it mentally.
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THAT IS THE RIGHT ANSWER
50 POINTS
Use the function f(x) to answer the questions.
f(x) = −16x2 + 22x + 3
Part A: What are the x-intercepts of the graph of f(x)? Show your work. (2 points)
Part B: Is the vertex of the graph of f(x) going to be a maximum or a minimum? What are the coordinates of the vertex? Justify your answers and show your work. (3 points)
Part C: What are the steps you would use to graph f(x)? Justify that you can use the answers obtained in Part A and Part B to draw the graph. (5 points)
Answers
work and answers below
Answer:
[tex]\text{Part A.}\\(-\frac{1}{8},0),\\(\frac{3}{2},0)\\\\\text{Part B.}\\(\frac{11}{16},\frac{169}{16})\\\\\text{Part C.}[/tex]
Draw a parabola concave down with vertex at [tex](\frac{11}{16},\frac{169}{16})[/tex]. Since the leading coefficient of the equation is -16, the parabola should appear thinner than its parent function [tex]y=x^2[/tex]. Ensure that the parabola passes through the points [tex](\(-\frac{1}{8},0)[/tex] and [tex](\frac{3}{2},0)[/tex].
Step-by-step explanation:
Part A:
The x-intercepts of a function occur at [tex]y=0[/tex]. Therefore, let [tex]y=0[/tex] and solve for all values of [tex]x[/tex]:
[tex]0=-16x^2+22x+3[/tex]
The quadratic formula states that the real and nonreal solutions to a quadratic in standard form [tex]ax^2+bx+c[/tex] is equal to [tex]x=\frac{-b\pm \sqrt{b^2-4ac}}{2a}[/tex].
In [tex]-16x^2+22x+3[/tex], assign:
[tex]a\implies -16[/tex] [tex]b\implies 22[/tex] [tex]c\implies 3[/tex]Therefore, the solutions to this quadratic are:
[tex]x=\frac{-22\pm\sqrt{22^2-4(-16)(3)}}{2(-16)},\\x=\frac{-22\pm 26}{-32},\\\begin{cases}x=\frac{-22+26}{-32}=\frac{4}{-32}=\boxed{-\frac{1}{8}},\\x=\frac{-22-26}{-32}=\frac{-48}{-32}=\boxed{\frac{3}{2}}\end{cases}[/tex]
The x-intercepts are then [tex]\boxed{(-\frac{1}{8},0)}[/tex] and [tex]\boxed{(\frac{3}{2},0)}[/tex].
Part B:
The a-term is negative and therefore the parabola is concave down. Thus, the vertex will be the maximum of the graph. The x-coordinate of the vertex of a quadratic in standard form [tex]ax^2+bx+c[/tex] is equal to [tex]x=\frac{-b}{2a}[/tex]. Using the same variables we assigned earlier, we get:
[tex]x=\frac{-22}{2(-16)}=\frac{-22}{-32}=\frac{11}{16}[/tex]
Substitute this into the equation of the parabola to get the y-value:
[tex]f(11/16)=-16(11/16)^2+22(11/16)+3,\\f(11/16)=\frac{169}{16}[/tex]
Therefore, the vertex of the parabola is located at [tex]\boxed{(\frac{11}{16},\frac{169}{16})}[/tex]
A driveway is in the shape of a rectangle 20 feet wide by 25 feet long.
(a)
Find the perimeter in feet.
(b)
Find the area in square feet.
Answers
To find the perimeter you have to add both the width and length x2 so it’s 20+25 =45
45x2=90
My flvs teacher said that she was asked to hold off on grading my assignment. She will give me a call back when when gets more information. Anyone have the same problem?
Answers
Answer:
yeah, teachers kinda suck
Use the Empirical Rule to answer the questions below:
The distribution of weights for newborn babies is approximately normally distributed with a mean of 7.6 pounds and a standard deviation of 0.7 pounds.
1. What percent of newborn babies weigh more than 8.3 pounds? %
2. The middle 95% of newborn babies weigh between and pounds.
3. What percent of newborn babies weigh less than 6.2 pounds? %
4. Approximately 50% of newborn babies weigh more than pounds.
5. What percent of newborn babies weigh between 6.9 and 9.7 pounds? %
Answers
Answer:
1. 16%
2. The middle 95% of newborn babies weigh between 6.2 and 9 pounds.
3. 2.5%
4. Approximately 50% of newborn babies weigh more than 7.6 pounds.
5. 83.85%
Step-by-step explanation:
The Empirical Rule states that, for a normally distributed random variable:
Approximately 68% of the measures are within 1 standard deviation of the mean.
Approximately 95% of the measures are within 2 standard deviations of the mean.
Approximately 99.7% of the measures are within 3 standard deviations of the mean.
In this problem, we have that:
Mean of 7.6 pounds, standard deviation of 0.7 pounds
1. What percent of newborn babies weigh more than 8.3 pounds?
7.6 + 0.7 = 8.3.
So more than 1 standard deviation above the mean.
The normal distribution is symmetric, which means that 50% of the measures are below the mean and 50% are above.
Of those above the mean, 100 - 68 = 32% are more than one standard deviation above the mean. So
[tex]0.32*0.5 = 0.16[/tex]
16% of newborn babies weigh more than 8.3 pounds.
2. The middle 95% of newborn babies weigh between and pounds.
Within 2 standard deviations of the mean, so:
7.6 - 2*0.7 = 6.2 pounds
7.6 + 2*0.7 = 9 pounds.
The middle 95% of newborn babies weigh between 6.2 and 9 pounds.
3. What percent of newborn babies weigh less than 6.2 pounds?
More than 2 standard deviations below the mean, which is 5% of the 50% below the mean, so:
[tex]p = 0.05*0.5 = 0.025[/tex]
2.5% of newborn babies weigh less than 6.2 pounds.
4. Approximately 50% of newborn babies weigh more than pounds.
Due to the symmetry of the normal distribution, the mean, so 7.6 pounds.
Approximately 50% of newborn babies weigh more than 7.6 pounds.
5. What percent of newborn babies weigh between 6.9 and 9.7 pounds?
6.9 = 7.6 - 0.7
9.7 = 7.6 + 3*0.7
Within 1 standard deviation below the mean(68% of the 50% below) and 3 standard deviations above the mean(99.7% of the 50% above). So
[tex]p = 0.68*0.5 + 0.997*0.5 = 0.8385[/tex]
83.85% of newborn babies weigh between 6.9 and 9.7 pounds.
The price of a car was decreased from $13,000 to $11,830. The price is decreased by what percentage?
Answers
Answer:
It is decreased by 9%
Step-by-step explanation:
First, find out how much money is decreased. To do this, subtract 13,000-11,830=1170. Finally, figure out how much percent 1170 is of the original price of $13,000.
The answer is 7%.
Hope this helps :)
What is the value of 3?
Answers
9514 1404 393
Answer:
3 ⇒ 12
Step-by-step explanation:
Apparently "a = b" in this case is used to mean f(a) = b. It appears as though the function is ...
f(x) = x(x+1)
Then f(3) = 3(3+1) = 3·4 = 12
_____
Additional comment
IMO this is a poor use of the equal sign, which should be reserved for situations where the left side expression has the same value as the right side expression.
The figures to the right are similar. Compare the first figure to the second. Give the ratio of the perimeters and the ratio of the areas
(integer or a simplified fraction)
Thank you!
Answers
9514 1404 393
Answer:
perimeter: 3 : 4area: 9 : 16Step-by-step explanation:
The perimeter ratio smaller : larger is the same as the side length ratio.
18 : 24 = 3 : 4 . . . smaller : larger perimeter ratio
The area ratio is the square of this.
3^2 : 4^2 = 9 : 16 . . . smaller : larger area ratio
a yogurt shop offers 7 different flavors of frozen yogurt and 11 different toppings. How many choices are possible for a single serving of frozen yogurt with one topping
Answers
answer: 77
Step-by-step explanation:
7×11=77
sorry if I'm wrong
Answer:
fijatebie nl aperguntaa
Step-by-step explanation:
Mr. Olaffsen opened a sandwich shop and a smoothie stand in his neighborhood.
The following table and equation show function f, representing Mr. Olaffsen's profit, in dollars, x months since opening the sandwich shop.
x 1 2 3 4 5 6 7
f(x) 12,000 15,500 18,000 19,500 20,000 19,500 18,000
The following table and equation show function g, representing Mr. Olaffsen's profit, in dollars, x months since opening the smoothie stand.
x 1 2 3 4 5 6 7
g(x) 9,300 12,000 14,100 15,600 16,500 16,800 16,500
Select the true statement.
A.
The difference between the maximum profit earned by the sandwich shop and the smoothie stand is $3,200.
B.
The difference between the maximum profit earned by the sandwich shop and the smoothie stand is $3,500.
C.
The difference between the maximum profit earned by the sandwich shop and the smoothie stand is $3,000.
D.
The difference between the maximum profit earned by the sandwich shop and the smoothie stand is $2,700.
Answers
Answer: the difference between the max is 3,200.
Step-by-step explanation:
20,000-16,800= 3,200
Answer:
the difference between the max is 3,200.
Step-by-step explanation:
20,000-16,800= 3,200
ESSE
Combine these radicals.
27-3
O √24
O 23
O-23
0 -3/2
Answers
here's the answer to your question
work out the value of (4√2)^2
Answers
Answer:
32
Step-by-step explanation:
(4[tex]\sqrt{2}[/tex] )²
= 4[tex]\sqrt{2}[/tex] × 4[tex]\sqrt{2}[/tex]
= 4 × 4 × [tex]\sqrt{2}[/tex] × [tex]\sqrt{2}[/tex]
= 16 × 2
= 32
Find an equation of the tangent to the curve at the point corresponding to the given value of the parameter. x=t−t−1, y=1+t2, t=1
Answers
Answer:
Step-by-step explanation:
First, I would find the point on the curve. By substituting t=1, I get (x, y). Next, I will try to eliminate the t and make a xy equation. In this case, the t's will cancel out in 'x=t-t-1" which wouldnt make this a curve. To find the equation of the tangent line, find the deretitave of the xy equation, and subsitute x in to find the slope at that point. Next, use point slope form to find the equation at the point.
How does the function notation compare with the standard notation?
Answers
A quality control inspector has drawn a sample of 18 light bulbs from a recent production lot. If the number of defective bulbs is 1 or more, the lot fails inspection. Suppose 30% of the bulbs in the lot are defective.
Required:
What is the probability that the lot will pass inspection?
Answers
Answer:
0.0016 = 0.16% probability that the lot will pass inspection.
Step-by-step explanation:
For each bulb, there are only two possible outcomes. Either it is defective, or it is not. The probability of a bulb being defective is independent of any other bulb, which means that the binomial probability distribution is used to solve this question.
Binomial probability distribution
The binomial probability is the probability of exactly x successes on n repeated trials, and X can only have two outcomes.
[tex]P(X = x) = C_{n,x}.p^{x}.(1-p)^{n-x}[/tex]
In which [tex]C_{n,x}[/tex] is the number of different combinations of x objects from a set of n elements, given by the following formula.
[tex]C_{n,x} = \frac{n!}{x!(n-x)!}[/tex]
And p is the probability of X happening.
Sample of 18 light bulbs
This means that [tex]n = 18[/tex]
30% of the bulbs in the lot are defective.
This means that [tex]p = 0.3[/tex]
What is the probability that the lot will pass inspection?
It will pass inspection if there are no defective bulbs, that is, we have to find P(X = 0). So
[tex]P(X = x) = C_{n,x}.p^{x}.(1-p)^{n-x}[/tex]
[tex]P(X = 0) = C_{18,0}.(0.3)^{0}.(0.7)^{18} = 0.0016[/tex]
0.0016 = 0.16% probability that the lot will pass inspection.
I need help with the question below
Answers
Answer:
a: 1/12
b: 1/6
c: 1/2
d: 1/2
e: 1/12
f: 1/3
Step-by-step explanation:
Which equation does the graph represent?
A. x^2 + y^2 = 4
B. x^2/3^2 + y^2/4^2 = 1
C. (X - 1)^2 / 3^2 + y^2/4^2 = 1
D.X^2 / 4^2 + (y + 1)^2 / 3^2 = 1
Answers
9514 1404 393
Answer:
B. x^2/3^2 + y^2/4^2 = 1
Step-by-step explanation:
The graph looks like a circle, but is not. It is a unit circle scaled by a factor of 3 in the x-direction and a factor of 4 in the y-direction. Thus, its equation is ...
(x/3)^2 +(y/4)^2 = 1
x^2/3^2 +y^2/4^2 = 1
what are the solutions to the quadratic equation (5y + 6)² = 24
Answers
Answer:
no solution
Step-by-step explanation:
25y² +36 = 24
(5y + 6) (5y + 6)
roots -6/5, -6/5
solution is always a positive root
Write an equivalent expression to 1/2 (2n+6).
Answers
Answer:
n+3
Step-by-step explanation:
1/2 × 2(n+3)=n +3
I hope this helps
Add O used 6 cups of whole wheat flour and eggs we flower and ax cups of white flour in the recipe what is the equation that can be used to find the value of Y the total amount of flour that adult used in the recipe and what are the constraints and the values of X and Y
Answers
Answer:
6x+y
Step-by-step explanation:
What is the solution to -41-2x + 6 = -24?
O x = 0
O x = 0 or x = -6
0 x = 0 or x = 6
Ono solution
Answers
Hello!
-41 - 2x + 6 = -24 <=>
<=> -35 - 2x = -24 <=>
<=> -2x = -24 + 35 <=>
<=> -2x = 11 <=>
<=> x = -11/2 or -5.5
Good luck! :)
The solution of the equation is only one solution.
What is Equation?Equations are mathematical statements with two algebraic expressions flanking the equals (=) sign on either side.
It demonstrates the equality of the relationship between the expressions printed on the left and right sides. LHS = RHS is a common mathematical formula.
Coefficients, variables, operators, constants, terms, expressions, and the equal to sign are some of the components of an equation. The "=" sign and terms on both sides must always be present when writing an equation.
We have,
-41 - 2x + 6 = -24
Now, solving for x we get
-41 + 6 -2x = -24
-35 - 2x = -24
-2x = -24 + 35
-2x = 11
x = -11/2
x= -5.5
As, the equation of linear and have x= -5.5.
Thus, the equation have only one solution.
Learn more about Equation here:
https://brainly.com/question/29538993
#SPJ7
f(x+h)-f(x)
Find the difference quotient
h
where h# 0, for the function below.
f(x) = 4x? -
-8
Simplify your answer as much as possible.
f(x + h) - f(x)
:
h
Х
Okay
Answers
9514 1404 393
Answer:
8x +4h
Step-by-step explanation:
[tex]\dfrac{f(x+h)-f(x)}{h}=\dfrac{(4(x+h)^2-8)-(4x^2-8)}{h}\\\\=\dfrac{(4x^2 +8xh+4h^2)-(4x^2-8)}{h}=\dfrac{8xh+4h^2}{h}\\\\=\boxed{8x+4h}[/tex]
If an orange seller bought 5 dozen oranges at the rate of tk.60 per four and sold them at the rate of tk50 per four,how much did he lose
Answers
Answer:
tk 30
Step-by-step explanation:
5 dozen = 5 * 12 = 60 oranges
12/4 = 3
total cost = 60 * 3 = tk.180
total sell = 50 * 3 = tk 150
total lose = 180 - 150 = tk 30
write your answer in simplest radical form
Answers
Answer:
3 =f
Step-by-step explanation:
Since this is a right triangle, we can use trig functions
tan theta = opp/ adj
tan 60 = f/ sqrt(3)
sqrt(3) tan 60 = f
sqrt(3) * sqrt(3) = f
3 =f
What is the value if x
Answers
Answer:
Step-by-step explanation:
Pls help me? I’m struggling
Answers
Answer: Number 1 is 150
Step-by-step explanation: If you put 72 / 48% in your calculator, you will get your answer.
What is the y-intercept of the line y+11= -2(x+5)?
Answers
Answer:
y-intercept is (0, -21)
Step-by-step explanation:
For y-intercept, x = 0:
[tex]{ \sf{y + 11 = - 2(0 + 5)}} \\ { \sf{y + 11 = - 10}} \\ { \sf{y = - 21}}[/tex]
The measures of the exterior angles of a convex pentagon can be represented as follows: angle 1=X, angle 2= 2x+9, angle 3=3x+4, angle 4=4x+11, angle 5=5x+18
Find the measure of each angle
