Complete question:
A police car is located 50 feet to the side of a straight road. A red car is driving along the road in the direction of the police car and is 130 feet up the road from the location of the police car. The police radar reads that the distance between the police car and the red car is decreasing at a rate of 75 feet per second. How fast is the red car actually traveling along the road.
Answer:
The red car is traveling along the road at 80.356 ft/s
Step-by-step explanation:
Given
Police car is 50 feet side off the road
Red car is 130 feet up the road
Distance between them is decreasing at the rate of 75 feet per sec
Let x be how far the police is off the road.
Let y be how far the red car is up the road.
Let h be the distance between the police and the red car.
This forms a right triangle so we can use the Pythagorean theorem, to solve for h
h² = x² + y²
h² = 50² + 130²
h² = 19400
h = √19400
h = 139.284 ft
Again;
Let dx/dt be how fast the police is traveling toward the road.
Let dy/dt be how fast the red car is traveling along the road.
Let dh/dt be how fast the distance between the police and the car is decreasing.
Recall that, h² = x² + y² (now differentiate with respect to time, t)
2h(dh/dt) = 2x(dx/dt) + 2y(dy/dt)
divide through by 2
h(dh/dt) = x(dx/dt) + y(dy/dt)
since the police car is not, dx/dt = 0
and dy/dt is the how fast is the red car actually traveling along the road
139.284(75) = 50(0) + 130(dy/dt)
10446.3 = 0 + 130(dy/dt)
dy/dt = 10446.3 / 130
dy/dt = 80.356 ft/s
Therefore, the red car is traveling along the road at 80.356 ft/s
Brainliest to whoever gets this correct Which of the following is equal to the rational expression when x ≠ -3? x^2-9/x+3
Answer:
see below
Step-by-step explanation:
We presume you want to simplify ...
[tex]\dfrac{x^2-9}{x+3}=\dfrac{(x-3)(x+3)}{x+3}=\boxed{x-3}[/tex]
__
The numerator is the difference of squares, so is factored accordingly. One of those factors cancels the denominator.
In two or more complete sentences, explain how to use ordered pairs of points in and to determine if and are inverses of each other.
by what rational number should we divide 22/7 so as to get the number -11/13?
Answer:
7/54
Step-by-step explanation:
let thenumber be x
then 22/7 /x = -11/27
= 22x/7 = -11/27
= x = -11*7/27*22 = 7/54
Hope it helps!!
You are standing 5 miles away from the peak. You look up at a 47-degree angle to the peak. How tall is the mountain? Hint: 5280 feet = 1 mile. Round your answer to the nearest foot.
Answer:
19272 feet
Step-by-step explanation:
We are given that the distance between the person and peak is 5 miles.
and angle is [tex]47^\circ[/tex] when we look up at the mountain peak.
The given situation is best represented as a right angled triangle as shown in the attached figure.
[tex]\triangle[/tex]IKJ where [tex]\angle K = 90^\circ[/tex]
IK is the mountain.
J is the point where we are standing.
Distance JI = 5 miles
[tex]\angle J = 47^\circ[/tex]
To find: Distance IK = ?
We can use trigonometric identities to find IK.
[tex]sin\theta = \dfrac{Perpendicular}{Hypotenuse}[/tex]
[tex]sinJ = \dfrac{IK}{JI}\\\Rightarrow sin47 = \dfrac{IK}{5}\\\Rightarrow IK = sin47^\circ \times 5\\\Rightarrow IK = 0.73 \times 5\\\Rightarrow IK = 3.65\ miles \\\Rightarrow IK = 3.65 \times 5280\ ft\\\Rightarrow IK = 19272\ ft[/tex]
Hence, height of mountain = 19272 ft
A File that is 242 megabytes is being downloaded.If the download is 12.9%complete,how many megabytes have been downloaded?Round your answer to the nearest tenth.
Answer:31
Step-by-step explanation: Since you are trying to find a percentage of a number all you have to do is multiply 242 by 12.9% and because you have to round to the nearest tenth it will be 31
Describe the steps to solve a rational equation. Create your own example and solve it following your steps. Then, provide an additional example for other people to try to solve as they reply to your post.
Answer:
Here is an exampls
Step-by-step explanation:
How do I solve 24-27?
Answer:
-3
Step-by-step explanation:
You find the difference between the numbers, which is 3. Then you make it negative since 24 is less than 27.
Which fraction is equivalent to 2/-6? -2/6 2/6 -2/-6 6/2
There are 5 gallons of distilled water in science supplies. If 8 students each use an equal amount of distilled water and there is 1 gallon left in supplies, how much will each student get?
Answer:
0.5 gallon
Step-by-step explanation:
let x refer to students
5 = 8x + 1
8x = 4
x= 0.5 gallon
A piece of wire of length 7070 is cut, and the resulting two pieces are formed to make a circle and a square. Where should the wire be cut to (a) minimize and (b) maximize the combined area of the circle and the square?
Answer:
a.x=39.2
b.Use whole wire as a circle
Step-by-step explanation:
We are given that
Length of piece of wire=70 units
Let length of wire used to make a square =x units
Length of wire used in circle=70- x
Side of square=[tex]\frac{perimeter\;of\;square}{4}=\frac{x}{4}[/tex]
Circumference of circle=[tex]2\pi r[/tex]
[tex]70-x=2\pi r[/tex]
[tex]r=\frac{70-x}{2\pi}[/tex]
Combined area of circle and square,A=[tex](\frac{x}{4})^2+\pi(\frac{70-x}{2\pi})^2[/tex]
Using the formula
Area of circle=[tex]\pi r^2[/tex]
Area of square=[tex](side)^2[/tex]
a.[tex]A=\frac{x^2}{16}+\frac{4900+x^2-140x}{4\pi}[/tex]
Differentiate w.r.t x
[tex]\frac{dA}{dx}=\frac{x}{8}+\frac{2x-140}{4\pi}[/tex]
[tex]\frac{dA}{dx}=0[/tex]
[tex]\frac{x}{8}+\frac{2x-140}{4\pi}=0[/tex]
[tex]\frac{\pi x+4x-280}{4\pi}=0[/tex]
[tex]\pi x+4x-280=0[/tex]
[tex]x(\pi+4)=280[/tex]
[tex]x=\frac{280}{\pi+4}[/tex]
x=39.2
Again differentiate w.r.t x
[tex]\frac{d^2A}{dx^2}=\frac{1}{8}+\frac{1}{2\pi}[/tex]>0
Hence, the combined area of circle and the square is minimum at x=39.2
b.When the wire is not cut and whole wire used as a circle . Then, combined area is maximum.
this is a grade 4 maths question. i need help with doing a model from this question as well. thank you! —————————————————- a rope was cut into 2 pieces. The first piece was twice the length of the second piece. If the first piece was 5m 50cm long what was the length of the rope before it was cut
Answer:825cm
Step-by-step explanation:550cm/2=275cm
275*3=825cm
how many nickels equal $18.45? (show your work)
Answer:
369
Step-by-step explanation:
One nickel = 0.05
0.05x=18.45
x=369
All math teachers are smart. Ms. Smith is your math teacher, so she is smart. What type of reasoning is this? inductive or deductive
Answer:
I believe it is Inductive Reasoning.
Step-by-step explanation:
Inductive Reasoning is a type of logical thinking that involves forming generalizations based on specific incidents you've experienced, observations you've made, or facts you know to be true or false.
Deductive Reasoning is a basic form of valid reasoning.
Find the common ratio for this geometric sequence. 243, 27, 3, 1/3, 1/27.
Answer:
1/9
Step-by-step explanation:
Since each next term is 1/9 of the last, the common ratio is 1/9. This can be confirmed by the fact that 243*1/9=27, 27*1/9=3, 3*1/9=1/3, and so on. Hope this helps!
Find the value of x and the value of y.
A r= 15, y = 10/3
B. r=20, p=10/3
C. x=20/3, y = 513
D. r=15, y =53
Answer:
Step by step solution:
Jalisa earned $71.25 today babysitting, which is $22.50 more than she earned babysitting yesterday. The equation d + 22.50 = 71.25 can be used to represent this situation, where d is the amount Jalisa earned babysitting yesterday. Which is an equivalent equation that can be used to find the amount Jalisa earned babysitting yesterday? 71.25 minus 22.50 = d 71.25 + 22.50 = d d + 71.25 = 22.50 d minus 22.50 = 71.25
Answer:
71.25 - 22.50 = d
Step-by-step explanation:
To find how much she earned yesterday, we subtract how much she earned today by the amount more she earned.
Answer:
A
Step-by-step explanation:
Please answer this correctly
Answer:
yes
Step-by-step explanation:
not every person is going to have the same opinion, so it is yes.
// have a great day //
Answer:
Yes, because if Pedro asked them the question "what do you think of public transportation?" the majority would probably say that they like it or something along those lines. This is biased because there may be other city inhabitants who don't think very highly of public transportation. Basically, what I'm trying to say is that not everyone will have the same opinion.
Brand name producers of aspirin claim that one advantage of their aspirin over generic aspirin is that brand name aspirin is much more consistent in the amount of active ingredient used. This in turn means that users can expect the same results each time they use the brand name aspirin, while the effects of the generic aspirin can be a lot more variable. A random sample of 200 brand name aspirin tablets had a mean and standard deviation of active ingredient of 325.01 and 10.12 mg. A second independent sample of 180 generic aspirin tablets was measured for the amount of active ingredient, and the mean standard deviation were 323.47 and 11.43 mg. Given that the amount of active ingredient is normally distributed for both the brand name and the generic aspirin, do these data support the brand name producers claim? Let alpha = 0.025.
Answer:
Step-by-step explanation:
The claim here is that the brand name aspirin is more consistent in the amount of active ingredient used than the generic aspirin.
This is a test of 2 independent groups. The population standard deviations are not known. Let μ1 be the mean amount of active ingredients in brand name aspirin and μ2 be the mean amount of active ingredients in generic name aspirin
The random variable is μ1 - μ2 = difference in the mean amount of active ingredients between the brand name and generic aspirin
We would set up the hypothesis.
The null hypothesis is
H0 : μ1 ≥ μ2 H0 : μ1 - μ2 ≥ 0
The alternative hypothesis is
H1 : μ1 < μ2 H1 : μ1 - μ2 < 0
This is a left tailed test
Since sample standard deviation is known, we would determine the test statistic by using the t test. The formula is
(x1 - x2)/√(s1²/n1 + s2²/n2)
From the information given,
x1 = 325.01
x2 = 323.47
s1 = 10.12
s2 = 11.43
n1 = 200
n2 = 180
t = (325.01 - 323.47)/√(10.12²/200 + 11.43²/180)
t = 1.24
1.237877
The formula for determining the degree of freedom is
df = [s1²/n1 + s2²/n2]²/(1/n1 - 1)(s1²/n1)² + (1/n2 - 1)(s2²/n2)²
df = [10.12²/200 + 11.43²/180]²/[(1/200 - 1)(10.12²/200)² + (1/180 - 1)(11.43²/180)²] = 1.53233946713/0.00537245359
df = 285
We would determine the probability value from the t test calculator. It becomes
p value = 0.108
Since alpha, 0.025 < than the p value, 0.108, then we would fail to reject the null hypothesis. Therefore, at 2.5% level of significance, these data support the brand name producers claim
It take Donna 15 minutes to complete 3 levels of Candy Crush. At this rate, how many levels will she complete in 3 hours?
Answer: she will have 36 levels completed
The population of a community is known to increase at a rate proportional to the number of people present at time t. If an initial population P0 has doubled in 3 years, how long will it take to triple
Rearrange the following steps in the correct order to locate the last occurrence of the smallest element in a finite list of integers, where the integers in the list are not necessarily distinct.
a. return location
b. min ≔a1 and location ≔1
c. min ≔ai and location≔i
d. procedure last smallest(a1,a2,...,an: integers)
e. If min >= ai then
Answer:
The rearranged steps is as follows:
d. procedure last smallest(a1,a2,...,an: integers)
b. min ≔a1 and location ≔1
e. If min >= ai then
c. min ≔ai and location≔i
a. return location
Step-by-step explanation:
The proper steps to perform the task in the question above is dbeca
Here, the procedure (or function) was defined along with necessary parameters
d. procedure last smallest(a1,a2,...,an: integers)
The smallest number is initialized to the first number on the list and its location is initialized to 1
b. min ≔a1 and location ≔1
The next line is an if conditional statement that checks if the current smallest number is greater than a particular number
e. If min >= ai then
If the above condition is true, the smallest value is assigned to variable min; it's location is also assigned to variable location
c. min ≔ai and location≔i
The last step returns the location of the smallest number
a. return location
please help and please show your work
Answer:
The volume of all 9 spheres is 301.6 [tex]in^3[/tex]
Step-by-step explanation:
Notice that three of the identical spheres fit perfectly along the 12 in side box, therefore we know that the diameter of each is 12 in/3 = 4 in.
Then the radius of each sphere must be 2 inches (half of the diameter). Now that we know the radius of each sphere, we use the formula for the volume of a sphere to find it:
[tex]V=\frac{4}{3} \pi R^3\\V=\frac{4}{3} \pi (2\,in)^3\\V=\frac{4}{3} \pi\, 8\,\,in^3\\V=\frac{32}{3} \pi\,\,in^3[/tex]
Now, the total volume of all nine spheres is the product of 9 times the volume we just found:
[tex]V_{all \,9}=9\,*\frac{32}{3} \pi\,\,in^3\\V_{all \,9}=96 \pi\,\,in^3\\V_{all \,9}\approx \,301.6\,\,in^3[/tex]
Teaching descriptive statistics. A study compared five different methods for teaching descriptive statistics. The five methods were traditional lecture and discussion, programmed textbook instruction, programmed text with lectures, computer instruction, and computer instruction with lectures. 45 students were randomly assigned, 9 to each method. After completing the course, students took a 1-hour exam.
a. What are the hypotheses for evaluating if the average test scores are different for the different teaching methods?
b. What are the degrees of freedom associated with the F-test for evaluating these hypotheses?
c. Suppose the p-value for this test is 0.0168. What is the conclusion?
Answer:
Step-by-step explanation:
a. The hypotheses are:
Null hypothesis: the average test scores are the same for the different teaching methods.
Alternative hypothesis: the average test scores are different for the different teaching methods.
b. To determine the degree of freedom for the F test: we must find two sources of variation such that we have two variances. The two sources of variation are: Factor (between groups) and the error (within groups) and add this up. Or use (N - 1). N is number in sample
c. With a p value of of 0.0168 and using a standard significance level of 0.05, we will reject the null hypothesis as 0.0168 is less than 0.05 and conclude that the average test scores are different for the different teaching methods.
What is the area of a shape with points a 5 -8 b 11, -8 c 11,0 d 6,-3 e 4,-3
Answer:
Area of the given figure is 51.5 square units.
Step-by-step explanation:
Area of rectangle OCBH = Length × width
= 11 × 8
= 88 square units
Area of trapezoid OGEF = [tex]\frac{1}{2}(b_1+b_2)\times h[/tex]
= [tex]\frac{1}{2}(\text{GE+OF)}\times (\text{OG})[/tex]
= [tex]\frac{1}{2}(3+6)\times 4[/tex]
= 18 units²
Area of trapezoid GCDE = [tex]\frac{1}{2}(\text{GC+DE)}\times (\text{GE})[/tex]
= [tex]\frac{1}{2}(7+2)\times 3[/tex]
= 13.5 units²
Area of triangle AFH = [tex]\frac{1}{2}(\text{Base})\times (\text{Height})[/tex]
= [tex]\frac{1}{2}(5)(2)[/tex]
= 5 units²
Area of polygon ABCDEF = Area of rectangle CBHO - (Area of trapezoid OGEF + Area of trapezoid GCDE + Area of triangle AFH)
= 88 - (18 + 13.5 + 5)
= 88 - 36.5
= 51.5 units²
Therefore, area of the given polygon is 51.5 units²
Based on the following construction which statement below
must NOT be true?
Answer:
B. AC = 2AB
hope it helps!
Step-by-step explanation:
AC is half of AB
so if the statement says AC is 2AB it suggests that AC is greater than AB
this is definitely false..
can 10/12 be simplified
Answer:
5/6
Step-by-step explanation:
10/12
Divide the top and bottom by 2
10/2 = 5
12/2 =6
the fraction becomes 5/6
Answer :
10/12
Reduce the fraction
= 5/6
All the angles in the diagram are measured to the nearest degree. Work out the upper bound and lower bound of angle x 59 degree 108 degree 81 degree X degree ??????
Answer: lower bound, x = 110.5°
upper bound, x = 113.5°
Step-by-step explanation:
There is no diagram but I am going to assume it is a quadrilateral since it has 4 angles. The sum of the angles of a quadrilateral is 360°.
Upper Lower
59° 58.5° ≤ a < 59.5
108° 107.5° ≤ b < 108.5°
81° 80.5° ≤ c < 81.5°
Total: 246.6° ≤ x < 249.5°
Subtract the lower and upper bound totals from 360° :
360.0 360.0
- 246.5 - 249.5
x = 1 1 3.5 1 1 0.5
↓ ↓
upper lower
bound bound
12x - y = -4
4x - 3y = -6 (1 point)
Answer:
Step-by-step explanation:
12x - y = -4 ----------------------(I)
4x - 3y = -6 ---------------------(II)
Multiply equation (I) by (-3)
(I)*(-3) -36x + 3y = 12
(II) 4x - 3y = - 6 {Add and y will be eliminated}
- 32x = 6
x = 6/-32
x = -3/16
Plugin the value of x in equation (I)
[tex]12*\frac{-3}{16} -y=-4\\\\3*\frac{-3}{4}-y=-4\\\\\frac{-9}{4}-y = -4\\\\-y=-4+\frac{9}{4}\\\\-y=\frac{-4*4}{1*4}+\frac{9}{4}\\\\-y=\frac{-16}{4}+\frac{9}{4}\\\\-y=\frac{-7}{4}\\\\y=\frac{7}{4}\\\\y=1\frac{3}{4}[/tex]
Rebecca is a real estate agent who would like to find evidence supporting the claim that the population mean market value of houses in the neighborhood where she works is greater than $250,000. To test the claim, she randomly selects 35 houses in the neighborhood and finds that the sample mean market value is $259,860 with a sample standard deviation of $24.922. The test statistic t for a hypothesis test of H0 : μ = 250.000 versus Ha : μ > 250.000 is t 2.34 , which has 34 degrees of freedom. If 0.01
A) Fail to reject the null hypothesis that the true population mean market value of houses in the neighborhood where Rebecca works is equal to $250,000.
B) Reject the null hypothesis that the true population mean market value of houses in the neighborhood where Rebecca works is equal to $250,000.
C) There is enough evidence at the α-: 0.05 level of significance to support the claim that the true population mean market value of houses in the neighborhood where Rebecca works is greater than $250,000.
D) There is not enough evidence at the α-_ 0.05 level of significance to suggest that the true population mean market value of houses in the neighborhood where Rebecca works is not equal to $250,000.
Answer:
There is enough evidence at the α-: 0.05 level of significance to support the claim that the true population mean market value of houses in the neighborhood where Rebecca works is greater than $250,000.
Step-by-step explanation:
We are given that Rebecca randomly selects 35 houses in the neighborhood and finds that the sample mean market value is $259,860 with a sample standard deviation of $24.922.
Let [tex]\mu[/tex] = population mean market value of houses in the neighborhood.
So, Null Hypothesis, [tex]H_0[/tex] : [tex]\mu[/tex] = $250,000 {means that the population mean market value of houses in the neighborhood where she works is equal to $250,000}
Alternate Hypothesis, [tex]H_A[/tex] : [tex]\mu[/tex] > $250,000 {means that the population mean market value of houses in the neighborhood where she works is greater than $250,000}
The test statistics that would be used here One-sample t-test statistics because we don't know about population standard deviation;
T.S. = [tex]\frac{\bar X-\mu}{\frac{s}{\sqrt{n} } }[/tex] ~ [tex]t_n_-_1[/tex]
where, [tex]\bar X[/tex] = sample mean market value = $259,860
s = sample standard deviation = $24,922
n = sample of houses = 35
So, the test statistics = [tex]\frac{259,860-250,000}{\frac{24,922}{\sqrt{35} } }[/tex] ~ [tex]t_3_4[/tex]
= 2.34
The value of t-test statistic is 2.34.
Also, P-value of the test statistics is given by;
P-value = P([tex]t_3_4[/tex] > 2.34) = 0.0137
Since our P-value is less than the level of significance as 0.0137 < 0.05, so we have sufficient evidence to reject our null hypothesis as it will fall in the rejection region due to which we reject our null hypothesis.
Therefore, we conclude that the population mean market value of houses in the neighborhood where she works is greater than $250,000.
Solve for b. -11b+7 = 40 Two step equations
Step-by-step explanation:
-11b + 7 = 40
-11b = 40 - 7
-11b = 33
b = 33/-11
b = - 3