Answer:
-3+8i
Step-by-step explanation:
The distance required to stop a car varies
directly as the square of its speed. If 250
feet are required to stop a car traveling 60
miles per hour, how many feet are required to
stop a car traveling 96 miles per hour?
Answer:
400
Step-by-step explanation:
The expression for the sum to 'n' terms of some Arithmetic Sequence are given beliw. Find the 'nth' term of each
i)n^2+2n
ii) n^2- 2n
Arithmetic Sequence
Find:'nth' term of each
i)n^2+2n
ii) n^2- 2n
Solution:1) Sum of first n terms = n² + 2n
We know that,
Sum of first n terms = n/2 * [ a + l ]
Where,
a is first term
l is nth or last term.
Substitute n = 1 to find the sum of first 1 terms i.e., first term (a) of the AP.
→ S₁ = a = (1)² + 2(1)
→ a = 1 + 2
→ a = 3
Hence,
→ n/2 * [ a + l ] = n² + 2n
→ a + l = n(n + 2) * 2/n
→ a + l = 2n + 4
→ l = 2n + 4 - a
→ l = 2n + 4 - 3
→ l = 2n + 1
Hence, the nth term is 2n + 1.
2)S(n) = n² - 2n
→ S₁ = a = (1)² - 2(1)
→ a = - 1
Hence,
→ n/2 * [ - 1 + l ] = n² - 2n
→ l - 1 = n(n - 2) * 2/n
→ l - 1 = 2n - 4
→ l = 2n - 4 + 1
→ l = 2n - 3
Hence, the nth term is 2n - 3.
I hope it will help you.
Regards.
Step-by-step explanation:
Series
The series of a sequence is the sum of the sequence to a certain number of terms. It is often written as Sn. So if the sequence is 2, 4, 6, 8, 10, ... , the sum to 3 terms = S3 = 2 + 4 + 6 = 12.
The Sigma Notation
The Greek capital sigma, written S, is usually used to represent the sum of a sequence. This is best explained using an example:
This means replace the r in the expression by 1 and write down what you get. Then replace r by 2 and write down what you get. Keep doing this until you get to 4, since this is the number above the S. Now add up all of the term that you have written down.
This sum is therefore equal to 3×1 + 3×2 + 3×3 + 3×4 = 3 + 6 + 9 + 12 = 30.
3
S 3r + 2
r = 1
This is equal to:
(3×1 + 2) + (3×2 + 2) + (3×3 + 2) = 24 .
The General Case
n
S Ur
r = 1
This is the general case. For the sequence Ur, this means the sum of the terms obtained by substituting in 1, 2, 3,... up to and including n in turn for r in Ur. In the above example, Ur = 3r + 2 and n = 3.
Arithmetic Progressions
An arithmetic progression is a sequence where each term is a certain number larger than the previous term. The terms in the sequence are said to increase by a common difference, d.
For example: 3, 5, 7, 9, 11, is an arithmetic progression where d = 2. The nth term of this sequence is 2n + 1 .
In general, the nth term of an arithmetic progression, with first term a and common difference d, is: a + (n - 1)d . So for the sequence 3, 5, 7, 9, ... Un = 3 + 2(n - 1) = 2n + 1, which we already knew.
The sum to n terms of an arithmetic progression
This is given by:
Sn = ½ n [ 2a + (n - 1)d ]
You may need to be able to prove this formula. It is derived as follows:
The sum to n terms is given by:
Sn = a + (a + d) + (a + 2d) + … + (a + (n – 1)d) (1)
If we write this out backwards, we get:
Sn = (a + (n – 1)d) + (a + (n – 2)d) + … + a (2)
Now let’s add (1) and (2):
2Sn = [2a + (n – 1)d] + [2a + (n – 1)d] + … + [2a + (n – 1)d]
So Sn = ½ n [2a + (n – 1)d]
Example
Sum the first 20 terms of the sequence: 1, 3, 5, 7, 9, ... (i.e. the first 20 odd numbers).
S20 = ½ (20) [ 2 × 1 + (20 - 1)×2 ]
= 10[ 2 + 19 × 2]
= 10[ 40 ]
= 400
Geometric Progressions
A geometric progression is a sequence where each term is r times larger than the previous term. r is known as the common ratio of the sequence. The nth term of a geometric progression, where a is the first term and r is the common ratio, is:
arn-1
For example, in the following geometric progression, the first term is 1, and the common ratio is 2:
1, 2, 4, 8, 16, ...
The nth term is therefore 2n-1
The sum of a geometric progression
The sum of the first n terms of a geometric progression is:
a(1 - rn )
1 – r
We can prove this as follows:
Sn = a + ar + ar2 + … + arn-1 (1)
Multiplying by r:
rSn = ar + ar2 + … + arn (2)
(1) – (2) gives us:
Sn(1 – r) = a – arn (since all the other terms cancel)
And so we get the formula above if we divide through by 1 – r .
Example
What is the sum of the first 5 terms of the following geometric progression: 2, 4, 8, 16, 32 ?
S5 = 2( 1 - 25)
1 - 2
= 2( 1 - 32)
-1
= 62
The sum to infinity of a geometric progression
In geometric progressions where |r| < 1 (in other words where r is less than 1 and greater than –1), the sum of the sequence as n tends to infinity approaches a value. In other words, if you keep adding together the terms of the sequence forever, you will get a finite value. This value is equal to:
a
1 – r
Example
Find the sum to infinity of the following sequence:
1 , 1 , 1 ,
1
,
1
,
1
, ...
2 4 8 16 32 64
Here, a = 1/2 and r = 1/2
Therefore, the sum to infinity is 0.5/0.5 = 1 .
So every time you add another term to the above sequence, the result gets closer and closer to 1.
Harder Example
The first, second and fifth terms of an arithmetic progression are the first three terms of a geometric progression. The third term of the arithmetic progression is 5. Find the 2 possible values for the fourth term of the geometric progression.
The first term of the arithmetic progression is: a
The second term is: a + d
The fifth term is: a + 4d
So the first three terms of the geometric progression are a, a + d and a + 4d .
In a geometric progression, there is a common ratio. So the ratio of the second term to the first term is equal to the ratio of the third term to the second term. So:
a + d = a + 4d
a a + d
(a + d)(a + d) = a(a + 4d)
a² + 2ad + d² = a² + 4ad
d² - 2ad = 0
d(d - 2a) = 0
therefore d = 0 or d = 2a
The common ratio of the geometric progression, r, is equal to (a + d)/a
Therefore, if d = 0, r = 1
If d = 2a, r = 3a/a = 3
So the common ratio of the geometric progression is either 1 or 3 .
If 72 is 9 times larger than 8, which statement below is true?
A) 8 is 72 times larger than 9
B) 72 is 8 times larger than 9
C) 9 is 8 times larger than 72
D) 8 is 9 times larger than 72
Name a pair of acute vertical angles
The cost to manufacture x number of chairs can be represented by the function C(x)=36x. In this context, what does the statement C(63)=2268 mean?
Answer:
The cost to manufacture 63 chairs, and that cost is 2268.
Step-by-step explanation:
Mathematical Models
The cost to manufacture x chairs is given as the math model:
C(x)=36x
For example, to manufacture 10 chairs, we write:
C(10)=36*10=360
According to the explained above, the statement C(63)=2268 means we are calculating the cost to manufacture 63 chairs, and that cost is 2268.
Which one?
A. B. C. or D?
Answer: D 3sqrt2
Step-by-step explanation:
6x3=18
Sqrt of 18 = 3sqrt2
2 (x-1 ) = x + 4 find x
Answer:
the answer it's x=6 i think
Find m 1 if m 2=47.6
Answer:
try 130.4, I got my answer by subtracting 47.6 with 180. How'd I get 180? the angles are obtuse so that means it'll add up to 180. Thus the answer is 130.4
Solve for y -x - 2y=8
Answer:y=4
Step-by-step explanation:
A recent article in the paper claims that business ethics are at an all-time low. Reporting on a recent sample, the paper claims that 45% of all employees believe their company president possesses low ethical standards. Suppose 20 of a company's employees are randomly and independently sampled and asked if they believe their company president has low ethical standards and their years of experience at the company. Could the probability distribution for the number of years of experience be modelled by a binomial probability distribution?
Answer:
Yes, the probability distribution for the number of years of experience can be modelled by a binomial probability distribution
Step-by-step explanation:
We are told that on a recent sample, the paper claims that 45% of all employees believe their company president possesses low ethical standards.
This means the chance of success is p = 45% = 0.45
Now, 20 of the company's employees are randomly and independently sampled. This means that for any amount of success within this sample number can be represented by;
P(X = x) = C(n, x) × p^(x) × (1 - p)^(n - x)
Where;
x is the number of possible successes
n is the number of trials
p is the chance or probability of success
C(n, x) is the number of possible combinations that could occur
This formula represents the binomial probability distribution formula.
So yes, the probability distribution for the number of years of experience can be modelled by a binomial probability distribution
What transformation keeps proportinality
−8 1/4+3 1/4
The "1/4" counts as a fraction. :)
Please help!!
3x + 5.9 = 14.6
What's the answer?
Answer: X=2.9
Step-by-step explanation:
Could someone show me how to do this?
Step-by-step explanation:
b - no:of students on bus
V - " " on van
so the eqtn is
12v+10b=698
14v+2b=244
so when you solve these two eqtns you get
V=9
b=59
Function h(x) = x + 4
If your input was 2, what is your output?
Answer:
h(2)=6
Step-by-step explanation:
just plug in 2 where you have an x, and you’d have 2 + 6, which equals 6
Select all sets to which the value belongs
√2- √2
Real Numbers/Irrational numbers/ Rational numbers/ Integers/Whole numbers/ Natural numbers.
Answer:
[tex] \sqrt{2} - \sqrt{2} = 0[/tex]
0 is real number, rational number, integers, whole numbers,
Is this the correct answer? Please someone help!!!
Answer:
yes
Step-by-step explanation:
same slope
Answer:
yes same slope
Step-by-step explanation:
Solve absolute value of x-2=4
Answer:
6
Step-by-step explanation:
2+4=6
you need to do the oppsite opporation and that the answer for example x-2=4 just add 2 and 4 and thats the answer that is aslo the same rule as divsion and multiplecation sorry for spelleng mistakes hope this helps!!!!!!
As an estimation we are told 5 miles is 8 km.
Convert 27.5 miles to km.
Answer:
44 km
Step-by-step explanation:
8/5 is the conversion between m and km which is 1.6 and then we can simply multiply 27.5 times 1.6 which is 44 km I hope this helps.
A youth group is selling snacks to raise money to attend their convention. Amy sold 2 pounds of candy, 3 boxes of cookies and 1 can of popcorn for a total sale of $65. Brian sold 4 pounds of candy, 6 boxes of cookies and 3 cans of popcorn for a total sale of $140. Paulina sold 8 pounds of candy, 8 boxes of cookies and 5 cans of popcorn for a total sales of $250. What is the cost of each item
Answer:
The cost of a can of popcorn is $10.
The cost of a box of cookies is $5.
The cost of a can of popcorn is $20
Step-by-step explanation:
First you must propose a system of equations, a set of two or more equations with several unknowns in which you want to find the value of each unknown so that all the equations of the system are fulfilled.
Defining the variables:
x: cost of one pound of candyy: cost of a box of cookiesz: cost of a can of popcornAmy sold 2 pounds of candy, 3 boxes of cookies and 1 can of popcorn for a total sale of $65. Then:
2*x + 3*y + 1*z=65 Equation 1
Brian sold 4 pounds of candy, 6 boxes of cookies and 3 cans of popcorn for a total sale of $140. So:
4*x + 6*y + 3*z=140 Equation 2
Paulina sold 8 pounds of candy, 8 boxes of cookies and 5 cans of popcorn for a total sales of $250. Then:
8*x + 8*y + 5*z=250 Equation 3
Then the system of equations is formed by these three equations.
A method to solve a system of equations is by means of the substitution method, which consists of isolating one of the two unknowns in an equation to substitute it in the other equation.
Isolating z from Equation 1:
[tex]z=65-2*x-3*y[/tex] Equation 4
Replacing in Equation 2:
4*x + 6*y + 3*(65 -2*x-3*y)=140
4*x + 6*y + 195 - 6*x - 9*y= 140
-2*x - 3*y=140-195
-2*x - 3*y=-55
2*x + 3*y= 55
and isolating x:
[tex]x=\frac{55-3*y}{2}[/tex] Equation 5
Replacing in Equation 4:
[tex]z=65-2*\frac{55-3*y}{2} -3*y[/tex]
z=65 - (55-3*y) - 3*y
z= 65 -55 + 3*y - 3*y
z= 10
So the cost of a can of popcorn is $10.
Replacing equation 5 and the value of z in equation 3:
8*[tex]\frac{55-3*y}{2}[/tex] + 8*y + 5*10=250
[tex]\frac{8}{2}[/tex]*(55 -3*y)+ 8*y + 5*10=250
4*(55 -3*y)+ 8*y + 5*10=250
4*55 - 4*3*y + 8*y + 50=250
220 - 12*y + 8*y + 50=250
-12*y + 8*y= 250 -220 - 50
-4*y= -20
[tex]y=\frac{-20}{-4}[/tex]
y= 5
So the cost of a box of cookies is $5.
Finally replacing the value of y in Equation 5 you get the value of x:
[tex]x=\frac{55-3*5}{2}[/tex]
[tex]x=\frac{55-15}{2}[/tex]
[tex]x=\frac{40}{2}[/tex]
x=20
Finally, the cost of a can of popcorn is $20
Suppose on a particular day, the probability (among the entire population) of getting into a car accident is 0.04, the probability of being a texter-and-driver is 0.14, and p(car accident or being a texter-and-driver)=0.15. Find the probability a person was in a car accident given that they are a texter-and-driver. Is this higher or lower than the probability among the general population and why?
Answer:
0.2143
Step-by-step explanation:
Let A be the event denote that getting into a car accident and B be the event denote being a texter-and-driver.
Thus, P(A)=0.04, P(B)=0.14.
P(A or B)=0.15.
We have to find P(A/B).
P(A/B)=P(A and B)/P(B)
P(A and B)= P(A)+P(B)-P(A or B)
P(A and B)=0.04+0.14-0.15
P(A and B)=0.03.
Thus, P(A/B)=0.03/0.14
P(A/B)=0.2143 (rounded to four decimal places)
Thus, the probability a person was in a car accident given that they are a texter-and-driver is 0.2143. This probability is higher than the probability among the general population because texting while driving is fatal.
Find the x-intercept and the y-intercept of the line below. Click on "None" if applicable.
The required x-intercept and y-intercept of the given line in the graph are 1 and -2 respectively.
What is an intercept of a line?The intercept of the line is defined as points where the line intersects the principle axes.
Here,
The x-intercept and y-intercept of the line are defined as the points where the given line cuts the coordinate axes.
So, from the above definition, the line intersects the x-axis at +1 and intersects the y-axis at -2.
Thus, the required x-intercept and y-intercept of the given line in the graph are 1 and -2 respectively.
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would u expect the product of 43.5 and 1.0001 to be greater than or less that 1 or equal to 43.5
Answer:
Greater
Step-by-step explanation:
since it has a 0.0001 and not just 1 its greater 43.5
A lake in East Texas was stocked with 3,000 trout in the year 2000. The number of fish in the lake is modeled by f(x) = 3000 + 100x, where x represents the number of years after 2000 until 2016. Which of the following is the most reasonable domain for the function?
Answer:
x_>0,_>3000
Step-by-step explanation:
I saw the answer key :)
The domain of a function is the set of input values the function can take.
The reasonable domain of the function is [0,16]
From the question, we understand that x represents the number of years after 2000 until 2016.
In 2000, the value of x is 0In 2016, the value of x is 16Hence, the reasonable domain of the function is [0,16]
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PLEASE HELP!! 20 POINTS!
Answer:
it attached in low quality im sorry :((
what is the equation for the line perpendicular to the line represented by the equation y=1/3x-2 that passes through the point (4,-7).
A. Y= -3x-2
B. Y= -3x-5
C. Y= 3x+2
D. Y= -3x+5
Answer:
y=-3x+5
bring (4,-7) in other three lines
you will know that it is unreasonable that
-7=-14
-7=-17
-7=14
The equation for the line perpendicular to the line represented by the equation [tex]y= \ \frac{1}{3} x-2[/tex] that passes through the point [tex](4,-7)[/tex] will be [tex]y=-3x+5[/tex].
What is equation for the perpendicular line ?Equation for the perpendicular line, the perpendicular lines have opposite-reciprocal slopes.
Now,
The equation of a perpendicular line must have a slope that is the negative reciprocal of the original slope.
Equation of a perpendicular line [tex]y=mx-b[/tex]
Here, [tex]m=[/tex] slope
So,
We have
[tex]y= \ \frac{1}{3} x-2[/tex]
Here,
[tex]m = \frac{1}{3}[/tex]
As mentioned above, we have to find the slope of perpendicular,
i.e.
(slope of perpendicular) [tex]m[/tex] [tex]=-3[/tex]
So,
[tex]y=mx-2[/tex]
[tex]y=(-3)x-b[/tex]
We have
Point [tex](4,-7)[/tex] through which line passes. i.e.
[tex]x=4[/tex]
[tex]y=(-7)[/tex]
Therefore,
[tex]-7=(-3)*4-b[/tex]
⇒ [tex]b=7-12[/tex]
[tex]b=(-5)[/tex]
So, Equation of a perpendicular line,
[tex]y=-3x+5[/tex]
So, Equation of a perpendicular line, [tex]y=-3x+5[/tex] which is derived from [tex]y=mx-b[/tex] .
Hence, we can say that the equation for the line perpendicular to the line represented by the equation [tex]y= \ \frac{1}{3} x-2[/tex] that passes through the point [tex](4,-7)[/tex] will be [tex]y=-3x+5[/tex].
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How many lines of symmetry, does this quadrilateral have
Answer:
im going to say 4 hope it helps
Step-by-step explanation:
WILL GIVE BRAINLIEST IF CORRECT
Answer:
la respuesta correcta es laC
han ku po ammo paumahin
ok, this is the last question I need help with(I think) please answer. I give Brainliest for best answer
Answer:
D) 132.67 (this seems to be the closest to the answer, I hope it helps)
Step-by-step explanation:
First, have the area of circle formula: A = π r²
Then, you need to find the radius to be able to complete the area formula. So, since you have the circumference, you will need to use it to find the radius:
C = 2 π r
40.82 = 2 π r
20.41 = π r
r = 6.496704777 . . . Do not round! Rounding will not give an exact answer!
Now that you have the radius, plug in:
A = π r²
= π (6.49 . . .)²
= π (42.20717296 . . .) Do not round! Rounding will not be exact!
= 132.5977445 . . .
≈ 132.6
What is the value of 7×7+23
Answer:
72
Step-by-step explanation:
7x7 = 49
49 + 23 = 72
PEMDAS causes the multiplication to come before the addition.