Answer: The constant of proportionality k is given by k=y/x where y and x are two quantities that are directly proportional to each other. Once you know the constant of proportionality you can find an equation representing the directly proportional relationship between x and y, namely y=kx, with your specific k.
Step-by-step explanation:
A motorboat travels 82 miles in 2 hours going upstream. It travels 106 miles going downstream in the same amount of time. What is the rate of the boat in still water and what is the rate of the current
let's recall d = rt, or namely distance = rate * time.
b = speed of the boat in still water
c = speed of the current
when going Upstream, the boat is not really going "b" fast, is really going slower, is going "b - c", because the current is subtracting speed from it, likewise, when going Downstream the boat is not going "b" fast, is really going faster, is going "b + c", because the current is adding its speed to it.
[tex]\begin{array}{lcccl} &\stackrel{miles}{distance}&\stackrel{mph}{rate}&\stackrel{hours}{time}\\ \cline{2-4}&\\ Upstream&82&b-c&2\\ Downstream&106&b+c&2 \end{array}\hspace{5em} \begin{cases} 82=(b-c)2\\\\ 106=(b+c)2 \end{cases} \\\\[-0.35em] ~\dotfill[/tex]
[tex]\stackrel{\textit{using the 1st equation}}{82=(b-c)2}\implies \cfrac{82}{2}=b-c\implies 41=b-c\implies \boxed{41+c=b} \\\\\\ \stackrel{\textit{substituting on the 2nd equation}}{106[~(41+c)+c~]2}\implies \cfrac{106}{2}=41+2c\implies 53=41+2c \\\\\\ 12=2c\implies \cfrac{12}{2}=c\implies \blacksquare~~ 6=c ~~\blacksquare~\hfill \blacksquare~~ \stackrel{41~~ + ~~6}{47=b} ~~\blacksquare[/tex]
help me solve please!!!!!!!!!
The probability of drawing a number card and then number card without replacement is 105/221 option first is correct.
What is probability?It is defined as the ratio of the number of favourable outcomes to the total number of outcomes, in other words, the probability is the number that shows the happening of the event.
The total number of cards = 52
Total number of cards printed number on it = 36
The probability of drawing a number card and then number card without replacement:
[tex]= \rm \dfrac{36}{52}\times \dfrac{35}{51}[/tex]
= 1260/2652
= 105/221
Thus, the probability of drawing a number card and then number card without replacement is 105/221 option first is correct.
Learn more about the probability here:
brainly.com/question/11234923
#SPJ1
Factor completely 16x8 − 1.
Answer:
Step-by-step explanation:
(4x^4 - 1)(4x^4 + 1)
(2x^2 - 1)(2x^2 + 1)(4x^4 + 1)
Verify (x-2) is a factor
of Q(x)=x²-3x²-4x+12
Answer:
(x - 2) is not a factor of Q(x)
Step-by-step explanation:
if (x - h) is a factor pf f(x) then f(h) = 0
if (x - 2) is a factor of Q(x) then Q(2) = 0
Q(2) = 2² - 3(2)² - 4(2) + 12
= 4 - 3(4) - 8 + 12
= 4 - 12 + 4
= - 8 + 4
= - 4
since Q(2) ≠ 0 then (x - 2) is not a factor of Q(x)
However , if the polynomial was meant to be
Q(x) = x³ - 3x² - 4x + 12 , then
Q(2) = 2³ - 3(2)² - 4(2) + 12
= 8 - 12 - 8 + 12
= 0
then (x - 2) is a factor of Q(x) = x³ - 3x² - 4x + 12
If you please tell me what this I will give 15 points and of thanks!
Answer:
y = x+8
Step-by-step explanation:
You find the difference between the value of y and value of x which is 8 so no matter what x is you always add 8 to get the y value. :)
Answer:
y = x + 8
Step-by-step explanation:
Find the difference between each x and y-value :
Let's take the pair (18, 26)
y = x + _26 = 18 + __ = 8What is the radius of a hemisphere with a volume of 281,250 2.14 cm^3
Answer:
:
Answer:the radius would be 88cm
Step-by-step explanation:
radius. r = base circumference. C = volume. V = curved surface area.
Pls help! I'm a bit confused!!
Answer:
Step-by-step explanation:
So whenever you see alphabets in math, these are called variable. Like the word suggests, variables can have different values depending on the problem.
For the first problem, the variable k equals 10, and the question asks you when k=10, what does that make k+26. All you do is substitute the value of k with the given value of k=10, and you get 10 + 26 = 36.
This way you can solve the rest of them.
Ask me if you get confused and we can work on rest of them.
Answer:
36529412.5112Step-by-step explanation:
Q1
k = 1010 + 2636Q2
n = 134(13)52Q3
a = 27 and b = 327/39Q4
x = 63(6) - 1418 - 144Q5
z = 2(2)² + 8.54 + 8.512.5Q6
x = 4 and y = 84(36 - 8)4(28)112PLEASE HELPPP!!!!
Which of the following is the best buy?
3 lb. for $5.13
2 lb. for $3.37
3.25 lb. for $5.53
1.5 lb. for $2.52
Answer:
3.25\
Step-by-step explanation:
Answer:
$2.52
Step-by-step explanation:
u have to at the lb. and the $ and which will give u more for a less price so we x out $5.53 and then 5.13.now all you have left is 2.52 and 3.37 and 3.37 is more than 2.52 and 2 lb. is more ik but u save more money by buying 1.5 lb.
hope this helps:)!!
Express x^2-5x+8 in the form (x-a)^2+b where a and b are integers
Answer:
[tex]f(x)=(x-\frac{5}{2})^2+\frac{7}{4}[/tex]
Step-by-step explanation:
Complete the square
[tex]f(x)=x^2-5x+8\\\\f(x)-1.75=x^2-5x+8-1.75\\\\f(x)-1.75=x^2-5x+6.25\\\\f(x)-1.75=(x-2.5)^2\\\\f(x)=(x-2.5)^2+1.75\\\\f(x)=(x-\frac{5}{2})^2+\frac{7}{4}[/tex]
If Kate has an apple, an orange, a pear, a banana, and a kiwi at home and she wants to bring three pieces of fruit to school, how many combinations of fruit can she bring?
125
3!
10
5!
Answer:
it 5
Step-by-step explanation:
Multiply. 2 5/8⋅(−4 3/4)
A. −12 15/32
B. −8 15/32
C. −7 3/8
D. −2 1/8
option b
see attachment for solution
hope it helps...!!!
WILL MARK BRAINLIEST . PLEASE HELP . Pigeons can fly at a rate of 168ft every 6 minutes, and ravens can fly at a rate of 472ft every 12.5 mins. Which unit rate, per hour, represents the speed of the faster bird?
Answer:
2,265.60 ft/hr
Step-by-step explanation:
168ft/6min = 28ft/min * 60min= 1,680ft/hr
472ft/12.5min= 37.76ft/min * 60min= 2,265.60ft/hr
SOMEONE HELP ME PLEASEE
Answer:
area: 165yd^2 perimeter:26yd or 33yd
Step-by-step explanation:
11ydx15yd= 165yd^2
11yd+15yd=26yd
Answer:
56.1, 36.2
Step-by-step explanation:
For this we need to use the Pythagorean Theorem, which is a^2+b^2=c^2. We have our a and c values, so we can make the equation 11^2+b^2=15^2, or 121+b^2=225. Next, we isolate b.
121+b^2=225
-121 -121
___ ___
0 104
b^2=104
Now, we have to find the square roots of both sides. If we do this, we get b= 10.2.
Now, we can find our perimeter:
11+15+10.2= 36.2
For area, the formula is 1/2(b)h (1/2 times the base and height), so:
1/210.2=5.1
5.1*11=56.1
Hope this helps!
A segment with endpoints at the center and on the circle.
Answer:
The set of points equidistant from a given point (the center). Radius : A segment with endpoints at the center and on the circle.
Step-by-step explanation:
Round 7.09 to the nearest tenth
Answer:
7.1
Step-by-step explanation:
To round 7.09 to the nearest tenth, you must use the hundredths' place value of 7.09, which is 9 and equal or more than 5. Therefore, the tenths value of 7.09 increases by 1 to 7.1.
Solve the following systems of equations. To unlock puzzle three
find the product of each solution (ordered pair -x and y value)
and then find the mean of all five products.
Answer:
Step-by-step explanation:
1,)
3x+y=4 <-Equation 1
2x-y=6 <-Equation 2
Step 1 Eliminating Y Multiply negative both side
-[3x +y = 4 ] -
-3x-y = -4 <-Equation 3
Equation 2 to Equation 3
2x-y=6
-
-3x-y = -4
= 5x = 10
x =2
Substituting X to Equation 1
3x+y=4
3(2) + y =4
6 + y = 4
y = -2
Therefore x =2 and y = -2
In 2014 the population of Kenya was estimated to be 45,121,040 with a growth rate of 2.7%. Question 1 Use the exponential growth formula to write an equation that estimates the population y in terms of the time t. Enter your answer in the box. Then apply the exponential growth formula to estimate the population of Kenya in 2020. Round to the nearest whole number
Answer:
y = 45,121,040×1.027^t
Step-by-step explanation:
An exponential growth equation is generally of the form ...
value at time t = (initial value)(growth factor)^t
where the growth factor is the multiplier for a period equal to one time unit.
Here, the initial value (in 2014) is 45,121,040. The growth factor is given as 1.027 (2.7% added per year), and we can define t as the number of years after 2014. Then our equation is ...
y = 45,121,040×1.027^t . . . . where t = years after 2014
What critical value of t* should be used for a 95% confidence interval for the population mean based on a random sample of 21 observations
To find the degrees of freedom in the given question, we have to take into consideration of the confidence interval as well as degrees of freedom. The critical t-value in this data set is 2.086
What is Confidence Interval?This is the range of values that we observe in our sample and for which we expect to find the value that accurately reflects the population.
We can also say that it is a range of values so defined that there is a specified probability that the value of a parameter lies within it.
Data;
sample size (n) = 21degree of freedom (df) = n-1 = 21 - 1 = 20At a 95% confidence level, the t is
α = 1 - 0.95
The critical t-value in this data set is 2.086
Learn more on t-value here;
brainly.com/question/4079902
#SPJ1
is 5/10 Equivalent to 1/4?
No
[tex] \frac{5}{10} = \frac{5 \times 1}{5 \times 2} = \frac{1}{2} \\ [/tex]
What is the value of y?
a.) 17.25
b.) 33
c.) 37
d.) 39
Answer:
a
Step-by-step explanation:
Answer:
a
Step-by-step explanation:
u know that the left triangle is not a right angles triangle so u cannot do Pythagoras and 27 is the other bottom side meaning that the length of the left triangle base is 20.25
Solve the following equation:-
2x(3+5)+6 x4
Answer:
40
Step-by-step explanation:
Using BODMAS
[tex](2 \times (8)) + (6 \times 4)[/tex]
[tex]16 + 24 = 40[/tex]
Answer:
40
Step-by-step explanation:
Using PEMDAS
ParenthesesExponentsMultiplicationDivisionAdditionSubtractionSimplify terms in the parentheses.
2 × (3 + 5) + 6 × 42 × 8 + 6 × 4Multiplying
2 × 8 + 6 × 416 + 24Adding
16 + 2440what's the difference between dy/dx and d/dx?
Answer:
There is a slight difference but the result is the same.
In the notation ddx(y) the ddx part is an operator which says ‘the function which is the differential with respect to x of ⋯’ and y is the function being operated on. The ddx and y are two separate entities in this notation.
In the notation dydx we mean the function that is the result of differentiating the function y with respect to x. In this case, there is only a single entity: dydx.
Both notations mean ‘the function which is the differential of function y by x
The length of a rectangular poster is 9 more inches than two times its width. The area of the poster is 161 square inches. Solve for the dimensions (length and width) of the poster.
Answer:
Width = 7 inches
Length = 23 inches
Step-by-step explanation:
Let :
length = 2x + 9width = xEquating to area :
(2x + 9)(x) = 1612x² + 9x = 1612x² + 9x - 161 = 02x² - 14x + 23x - 161 = 02x(x - 7) + 23(x - 7) = 0x - 7 = 0x = 7Dimensions are :
Width = 7 inchesLength = 2(7) + 9Length = 23 inchesAnswer:
Length: 23 inches
Width: 7 inches
Explanation:
Width: wLength: 2w + 9Area of rectangle: Length × Width(2w + 9) × (w) = 1612w² + 9w - 161 = 02w² + 23w - 14w -161 = 0w(2w + 23) -7(2w +23) = 0w = 7, -11.5As length measure cannot be negative. Width is +7 inches
Length: 2w + 9 = 2(7) + 9 = 14 + 9 = 23
how do u find the surface area of all the prisms?
is −1.28 a rational number?
The number -1.28 is rational if it is an integer or decimal, so yes it is.
Answer:
we have 1.28 with bar above 28 signifying that the number can also be written as 1.28282828 The mixed number is then equal to,
1 and 28/99 or 1 and 28 over 99
Therefore, the answer to this item is the second choice.
Step-by-step explanation:
My brother helped me with this one
Jeremy finished 3/5 of his homework what percent of homework did he finish
Answer:
60%
Step-by-step explanation:
Percent means per hundred. Change to "per hundred"
3/5 = 6/10 = 60/100
3/5 is 60%
OR
Divide 3/5 means 3÷5...
3÷5 = .6
Change decimal to percent by multiplying by 100.
.6 × 100 = 60
60%
Answer:
60%
Step-by-step explanation:
well if they only finished 3/5 it’s going to be
60/100 = 60%
Help me with this extremely hard differentiation question , [Scroll] >>
[tex]\huge\frac{d}{dx}[\sum_{n=0}^{∞}[(\frac{(-1) ^ {n}}{(2n+1)!})(\frac{1}{1+e^{x}})^{2n+1}] ][/tex]
Answer:
[tex]f'(x)=\displaystyle -\frac{e^x}{(1+e^x)^2}\cos\biggr(\frac{1}{1+e^x}\biggr)[/tex]
Step-by-step explanation:
Recall the power series [tex]\sin(x)=\displaystyle \sum\limits^\infty_{n=0}(-1)^n\frac{x^{2n+1}}{(2n+1)!}[/tex].
In this case, [tex]x[/tex] is replaced with [tex]\displaystyle \frac{1}{1+e^x}[/tex], so our power series actually works out to be [tex]\displaystyle \sin\biggr(\frac{1}{1+e^x}\biggr) =\sum\limits^\infty_{n=0}(-1)^n\frac{\bigr(\frac{1}{1+e^x}\bigr)^{2n+1}}{(2n+1)!}[/tex]! Amazing, huh?
Now, we find the derivative of the function by using the chain rule:
[tex]\displaystyle \frac{d}{dx}\sin\biggr(\frac{1}{1+e^x}\biggr)=\frac{d}{dx}\biggr(\frac{1}{1+e^x}\biggr)*\cos\biggr(\frac{1}{1+e^x}\biggr)=-\frac{e^x}{(1+e^x)^2}\cos\biggr(\frac{1}{1+e^x}\biggr)[/tex]
You didn't specify if you just wanted the derivative of the series to be a function or a series, so I'm going to assume you want the function. Let me know if there's more to your problem.
Does anyone know the answer???
Answer:
That's the right answer
Step-by-step explanation:
Hope to help
mark me as brainlinest plss
How to do 2/5 = (x-3)/(7x+15)
Answer:
[tex]x = - 5 [/tex]
Step-by-step explanation:
To work out this question you have to first cross multiply.
[tex] \frac{2}{5} = \frac{(x - 3)} {(7x + 15)} \\ \\ 2(7x + 15) = 5(x - 3)[/tex]
When you cross multiply you will get the equation above. Therefore
[tex](2 \times 7x) + (2 \times 15) = (5 \times x) \\ - (5 \times 3) \\ \\ 14x + 30 = 5x - 15 \\ \\ 14x - 5x = - 30 - 15 \\ \\ 9x = - 45[/tex]
Therefore
[tex] \frac{9}{9} x = \frac{ - 45}{9} \\ \\ x = - 5[/tex]
Answer:
x = -5
Step by step:
multiply both side by 7x + 15.
2/5 (7x+15)= x − 3
Simplify 2)5 (7x+15) to 2(7x+15)/5.
2(7x+15)/5= x - 3
multiply both sides by 5.
2(7x+15)= 5x - 15
Expand.
14x+30= 5x - 15
subtract 5x from both sides.
14x+30−5x= − 15
Simplify 14x + 30 - 5x14x + 30−5x to 9x + 309x + 30.
9x+30= - 15
Subtract 30 from both sides.
simplify
x = -5
Need help please answer ASAP!
Answer:
39. (4) 4 1/16
Step-by-step explanation:
Simplifying
f(x) = 4x⁰ + (4x)⁻¹Any term to the power is equal to 1f(x) = 4(1) + 1/4xSubstituting x = 4
f(4) = 4 + 1/4(4)f(4) = 4 + 1/16f(4) = 4 1/16(4) 4 1/16