Answer:
Step-by-step explanation:
This is a related rates problem from calculus using implicit differentiation. The main equation is Pythagorean's Theorem. Basically, what we are looking for is [tex]\frac{dx}{dt}[/tex] when y = 6 and [tex]\frac{dy}{dt}=-2[/tex].
The equation for Pythagorean's Theorem is
[tex]x^2+y^2=c^2[/tex] where x and y are the legs and c is the hypotenuse. The length of the hypotenuse is 10, so when we find the derivative of this function with respect to time, and using implicit differentiation, we get:
[tex]2x\frac{dx}{dt}+2y\frac{dy}{dt}=0[/tex] and divide everything by 2 to simplify:
[tex]x\frac{dx}{dt}+y\frac{dy}{dt}=0[/tex]. Looking at that equation, it looks like we need a value for x, y, [tex]\frac{dx}{dt}[/tex] and [tex]\frac{dy}{dt}[/tex].
Since we are looking for [tex]\frac{dx}{dt}[/tex], that can be our only unknown and everything else has to have a value. So what do we know?
If we construct a right triangle with 10 as the hypotenuse and use 6 for y, we can solve for x (which is the only unknown we have, actually). Using Pythagorean's Theorem to solve for x:
[tex]x^2+6^2=10^2[/tex] and
[tex]x^2+36=100[/tex] and
[tex]x^2=64[/tex] so
x = 8.
NOW we can fill in the derivative and solve for [tex]\frac{dx}{dt}[/tex].
Remember the derivative is
[tex]x\frac{dx}{dt}+y\frac{dy}{dt}=0[/tex] so
[tex]8\frac{dx}{dt}+6(-2)=0[/tex] and
[tex]8\frac{dx}{dt}-12=0[/tex] and
[tex]8\frac{dx}{dt}=12[/tex] so
[tex]\frac{dx}{dt}=\frac{12}{8}=\frac{6}{4}=\frac{3}{2}=1.5 m/sec[/tex]
PLZ ANSWER ASAP
(look at images below, from khan)
Answer:
D Replace on equation with sum /difference of both equations
The systems are still the same
Step-by-step explanation:
5x + y = 3
4x - 7y = 8
Subtract the second equation from the first
5x + y = 3
-(4x - 7y = 8)
-----------------
x +8y = -5
The second equation in system B is the first equation in system a minus the second equation in system A
We added the same thing to each side of the equation so the the system is still the same
the polygons in each pair are similar find the scale factor smaller figure to the larger
Answer:
smaller figure/larger figure = ½
Step-by-step explanation:
The scale factor = any of the side length of the smaller figure / the corresponding side length of the larger figure
Side length of smaller figure = 3
Corresponding sides length of larger figure = 6
Scale factor = smaller figure/larger figure = 3/6
Simplify
Scale factor = smaller figure/larger figure = ½
On a map, the scale shown is 1 inch : 5 miles. If an island is 2.5 squire inches on the map, what is the actual area of the island? The actual island's area is square miles.
Answer:
62.5 square miles
Step-by-step explanation:
if the scale is 1 in. = 5 mi, then 1 square in. = 25 square miles
so if 1 in^2 = 25 mi^2
then you make a proportion
25/1 = x/2.5
(the square inches on the bottom and the square miles on top)
solving for x gives you
x=62.5 square miles
What is lim j(x)?
X-3
9514 1404 393
Answer:
(b) 4
Step-by-step explanation:
The point (3, 4) is a "hole" in the graph. The function approaches the value y=4 from either direction, so that is the limit as x → 3.
[tex]\displaystyle\lim_{x\to3}f(x)=4[/tex]
10) Find three numbers whose product is -72. You may use integers from -10 to 10. Give two
examples
Answer:
Step-by-step explanation:
-8 * 9 * 1
If you are going to get - 72, you need to have an odd number of minus signs.
4 * 3 * - 6
You must be careful of the limits. You can't use something like 36 * 2 * 1 because the numbers don't fall within +/- 10
You could use 6*6*-2
Which of the following methods of sampling is an example of a stratified random sample?
A. Randomly choosing a name from a list of names in the population and then choosing every tenth name thereafter.
B. From 500 names of members of a population in a hat drawing 50 names from the hat without looking.
C. Dividing a target population of students by grade level and choosing the first 25 names from each group.
D. Dividing a population of adults into males and females and randomly choosing a sample proportional to the numbers in each group.
Answer: D
Step-by-step explanation:
Answer: D
Step-by-step explanation:
What are the values of a, b, and c in the quadratic equation 0 = one-halfx2 – 3x – 2?
a = one-half, b = 3, c = 2
a = one-half, b = –3, c = –2
a = one-half, b = 3, c = –2
a = one-half, b = –3, c = 2
Answer:
b
Step-by-step explanation:
ax^2+bx+c=0
1/2x^2-3x-2=0
Answer:
B
Step-by-step explanation:
Diana get a gift card with a value of $55, and her favorite drink cost $2.20. How many plain black coffee can she buy with the gift card
Answer:
Twouufyjughgyuioiu567uhu888
Answer:
55/2.20=25 so 25 black coffees
Step-by-step explanation:
strontium-90 is a radioactive material that decays according to the function A(t)=A0e−0.0244t, where A0 is the initial amount present and A is the amount present at time t (in years). Assume that a scientist has a sample of 400 grams of strontium-90.
(a) What is the decay rate of strontium-90?
(b) How much strontium-90 is left after 30 years?
(c) When will only 100 grams of strontium-90 be left?
(d) What is the half-life of strontium-90?
(a) The decay rate of strontium-90 is nothing%.
(Type an integer or a decimal. Include the negative sign for the decay rate.)
Answer:
Step-by-step explanation:
The decay rate of strontium-90 is -.0244 as given.
For b., we have to use the formula to find out how much is left after 30 years. This will be important for part d.
[tex]A(t)=400e^{-.0244(30)}[/tex] which simplifies a bit to
A(t) = 400(.4809461353) so
A(t) = 192.4 g
For c., we have to find out how long it takes for the initial amount of 400 g to decay to 100:
[tex]100=400e^{-.0244t}[/tex]. Begin by dividing both sides by 400:
[tex].25=e^{-.0244t[/tex] and then take the natural log of both sides:
[tex]ln(.25)=lne^{-.0244t[/tex] . The natural log and the e cancel each other out since they are inverses of one another, leaving us with:
ln(.25) = -.0244t and divide by -.0244:
61.8 years = t
For d., we figured in b that after 30 years, 192.4 g of the element was left, so we can use that to solve for the half-life in a different formula:
[tex]A(t)=A_0(.5)^{\frac{t}{H}[/tex] and we are solving for H. Filling in:
[tex]192.4=400(.5)^{\frac{30}{H}[/tex] and begin by dividing both sides by 400:
[tex].481=(.5)^{\frac{30}{H}[/tex] and take the natural log of both sides, which allows us to pull the exponent out front. I'm going to include that step in with this one:
ln(.481) = [tex]\frac{30}{H}[/tex] ln(.5) and then divide both sides by ln(.5):
[tex]\frac{ln(.481)}{ln(.5)}=\frac{30}{H}[/tex] and cross multiply and isolate the H to get:
[tex]H=\frac{30ln(.5)}{ln(.481)}[/tex] and
H = 28.4 years
I need help with the answer
Answer:
Option B, x ≈ -2.25
Step-by-step explanation:
3^x-2=(x-1)/(x^2+x-1)
or x ≈ -2.21166
so it's closest to the answer of the 2nd option
A painter can paint 36 feet of molding per hour. How many inches of molding can he paint per hour?
Answer:
432 inches
Step-by-step explanation:
We need to convert feet to inches
1 ft = 12 inches
36 ft * 12 inches/ 1 ft = 432 inches
of a loaf of brown bread costs R6, how much will 4 halves cost?
Answer:
R12
Step-by-step explanation:
Answer: R12
Explanation:
Cost of 1 loaf = R6
Cost of 4 halves = 6/2×4
= 6 × 2
= R12
Please click thanks and mark brainliest if you like
Which graph has the solutions -1 and 4?
a.
On a coordinate plane, a parabola opens up and goes through (negative 4.2, 0) and (0, negative 1).
c.
On a coordinate plane, a parabola opens up and goes through (negative 4, 0) and (1, 0).
b.
On a coordinate plane, a parabola opens up and goes through (0, negative 3) and (4.5, 0).
d.
On a coordinate plane, a parabola opens up and goes through (0, negative 1) and (4, 0).
Please select the best answer from the choices provided
A
B
C
D
Answer:
graph d
in graph d, the line intersects the x axis twice at (-1,0) and (4,0), so those two are the solutions of the graph
Larry made 14 baskets out of 21 attempts in a recent basketball game. If Scott attempted 24 baskets and made the same proportion of baskets as Larry, how many baskets did Scott make?
Scott made
baskets.
Answer:
16 baskets
Step-by-step explanation:
Create a proportion where x is the number of baskets that Scott made:
[tex]\frac{14}{21}[/tex] = [tex]\frac{x}{24}[/tex]
Cross multiply and solve for x:
21x = 336
x = 16
So, Scott made 16 baskets.
What is the equation of this graph
Answer:
y-1=x^2
Step-by-step explanation:
That is the equation of a parabola with vertex at (0,1). The equation is y-1=x^2.
Find the value of x.
A. 4
B. 2
C. 3
D. 6
Answer:
b
Step-by-step explanation:
2x4=8 3x2=6 2x2=4
there all diviseble by 2
therfore ur answer is b
Answer:
the answer is 4
Step-by-step explanation:
Air is being pumped into a spherical balloon at a rate of 5 cm^3/min. Determine the rate at which the radius of the balloon is increasing when the diameter of the balloon is 20 cm
0.08 cm/min
Step-by-step explanation:
Given:
[tex]\dfrac{dV}{dt}=5\:\text{cm}^3\text{/min}[/tex]
Find [tex]\frac{dr}{dt}[/tex] when diameter D = 20 cm.
We know that the volume of a sphere is given by
[tex]V = \dfrac{4\pi}{3}r^3[/tex]
Taking the time derivative of V, we get
[tex]\dfrac{dV}{dt} = 4\pi r^2\dfrac{dr}{dt} = 4\pi\left(\dfrac{D}{2}\right)^2\dfrac{dr}{dt} = \pi D^2\dfrac{dr}{dt}[/tex]
Solving for [tex]\frac{dr}{dt}[/tex], we get
[tex]\dfrac{dr}{dt} = \left(\dfrac{1}{\pi D^2}\right)\dfrac{dV}{dt} = \dfrac{1}{\pi(20\:\text{cm}^2)}(5\:\text{cm}^3\text{/min})[/tex]
[tex]\:\:\:\:\:\:\:= 0.08\:\text{cm/min}[/tex]
What is 20×10 to the third power equal
Find the remainder when f(x)=x3−4x2−6x−3 f ( x ) = x 3 − 4 x 2 − 6 x − 3 is divided by x+1
Answer:
The remainder is -2.
Step-by-step explanation:
According to the Polynomial Remainder Theorem, if we divide a polynomial P(x) by a binomial (x - a), then the remainder of the operation will be given by P(a).
Our polynomial is:
[tex]P(x) = x^3-4x^2-6x-3[/tex]
And we want to find the remainder when it's divided by the binomial:
[tex]x+1[/tex]
We can rewrite our divisor as (x - (-1)). Hence, a = -1.
Then by the PRT, the remainder will be:
[tex]\displaystyle\begin{aligned} R &= P(-1)\\ &=(-1)^3-4(-1)^2-6(-1)-3 \\ &= (-1)-4(1)+(6)-3 \\ &= -2 \end{aligned}[/tex]
The remainder is -2.
A basic cellular package costs $30/month for 60 minutes of calling with an additional charge of $0.40/minute beyond that time. The cost function C (2) for using x minutes would be • If you used 60 minutes or less, i.e. if if x < 60, then C (x) = 30 (the base charge). If you used more than 60 minutes, i.e. (x – 60 minutes more than the plan came with, you would pay an additional $0.40 for each of those (x – 60 minutes. Your total bill would be C (x) = 30 + 0.40 (x – 60). If you want to keep your bill at $50 or lower for the month, what is the maximum number of calling minutes you can use? minutes. The maximum calling minutes you can use is ? Number
Answer:
The maximum number of minutes to keep the cost at $50 or less is 110 minutes
Step-by-step explanation:
Given
[tex]C(x) = 30[/tex] ---- [tex]x < 60[/tex]
[tex]C(x) = 30 + 0.40(x - 60)[/tex] --- [tex]x \ge 60[/tex]
Required
[tex]C(x) = 50[/tex] ---- find x
We have:
[tex]C(x) = 30 + 0.40(x - 60)[/tex]
Substitute 50 for C(x)
[tex]50 = 30 + 0.40(x - 60)[/tex]
Subtract 30 from both sides
[tex]20 = 0.40(x - 60)[/tex]
Divide both sides by 0.40
[tex]50 = x - 60[/tex]
Add 60 to both sides
[tex]110 = x[/tex]
[tex]x =110[/tex]
Example 2.20
Solution
After 7% discount, Faizal get RM1,930 from a bank. He then promised to pay the bank RM2,000
after x days. Determine the value of x.
Kaspersk
Th
The period of days (value of x) for which Faizal promised to pay the bank RM 2,000 after getting 7% discounted present value of RM 1,930 is 180 days.
The value of x is the period of days (number of days) that the loan from the bank will last before Faizal, who received RM 1,930 discounted at 7%, would repay the bank the principal and interest of RM 2,000.
This implies that Faizal is paying an interest of RM 70 (RM 2,000 - RM 1,930), since he borrowed RM 1,930 and will repay RM 2,000.
Data and Calculations:
Present value of loan received = RM 1,930
Discount rate per year = 7%
Future value of the loan to be repaid to the bank = RM 2,000
Interest expense for one year based on 7% = RM 140 (RM 2,000 x 7%)
Interest expense for 180 days or 6 months = RM 70 (RM 2,000 - RM 1,930) or (RM 2,000 x 7%) x 180/360
Interest expense that equals RM 70 will be half of a year or 180 days (RM 140 * 180/360)
Thus, the period of days (x) that will lapse for Faizal to repay the bank is 180 days or half of a year (6 months).
Learn more about time period of a loan here: https://brainly.com/question/19118285
Factorize p2-15q-5p+2pq
Hope it's help you!!!!!!
Which of the following is correctly written in Standard Form? −3x + 7y = 12, y = 3/7x + 6 ,5x − 4y = 9 ,3/7x + 2y =9
Use the distributive property to simplify
the equation below.
с
8(2a + 4b - c)
[? ]a + [ ]b - [
[ ]
Answer:
16a +32b - 8c
Step-by-step explanation:
8(2a + 4b - c)
Distribute
8*2a + 8*4b+ 8*(-c)
16a +32b - 8c
Answer:
16a + 32b - 8c
Step-by-step explanation:
You bring 8 inside the parenthesis and then multiply it with everything. so for a you put 16, b you put 32 and c you put 8
Instructions: Given the vertex of a quadratic function, find the axis
of symmetry.
Vertex: (5,7)
Taking into account the definition of axis of simmetry and vertexn the axis of symmetry is x = 5.
So, first of all, you must know what a quadratic function is. Every quadratic function can be expressed as follows:
f(x) = a*x² + b*x + c
where a, b and c are real numbers.
Axis of symetryThe graph of a quadratic function is a parabola. Every parabola is a symmetric curve with respect to a horizontal line called the axis of symmetry.
That is, the axis of symmetry is an imaginary line that passes through the middle of the parabola and divides it into two halves that are equal of each other.
In other words, the axis of symmetry of a parabola is a vertical line that divides the parabola into two equal halves and always passes through the vertex of the parabola.
VertexThe point of intersection of the axis of symmetry with the parabola is called the vertex.
The axis of symmetry always passes through the vertex of the parabola. The x-coordinate of the vertex is the equation of the axis of symmetry of the parabola.
SummaryBeing the vertex of the quadratic function (5,7), where the vertex on the x-axis has a value of 5 and on the y-axis a value of 7, the axis of symmetry is x = 5.
Learn more with this examples:
https://brainly.com/question/2799442?referrer=searchResultshttps://brainly.com/question/20862832?referrer=searchResultshttps://brainly.com/question/15266651?referrer=searchResultsSimplify the algebraic expression by combining like (or similar) terms.
2x−y2+3−3y2+2x+1
Answer:
-4y^2 + 4x +4
Step-by-step explanation:
add -y^2 and -3y^2 = -4y^2
add 2x + 2x = 4x
add 3+1 = 4
and then rearrange
Hi! I would appreciate if you could solve this for me. The question I need help with is question 41. Thank you. :)
Answer:
Expression: 7+7+9.5+6+9.5
Evaluation: 39 cm
Step-by-step explanation:
Let's write the numerical expression for the figure to the right. The perimeter is the addition of all sides of the figure. Therefore, we write 7+7+9.5+6+9.5 for our expression.
Now, to evaluate the expression, we just add them together. 7+7+9.5+6+9.5=39 cm.
Can someone please help with 25 , please put the way you got it. Please no links it’s serious
Answer:
X * 0.8 = $64
x = $80
Step-by-step explanation:
Please help with Question 2b
Answer:
MUST BE IN HLA, NOT FROM C TO ASSEMBLY.
PROGRAM 6: Same
Write an HLA Assembly language program that implements a function which correctly identifies when all four parameters are the same and returns a boolean value in AL (1 when all four values are equal; 0 otherwise). This function should have the following signature:
procedure theSam
The probability of winning a raffle is 2/5. What is the probability of not winning the raffle?
0
3/5
2/5
Answer:
3/5
Step-by-step explanation:
um 3/5+2/5 = 1
