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Suppose you are an event coordinator for a large performance theater. One of the hottest new Broadway musicals has started to tour and your city is the first stop on the tour. You need to supply information about projected ticket sales to the box office manager. The box office manager uses this information to anticipate staffing needs until the tickets sell out. You provide the manager with a quadratic equation that models the expected number of ticket sales for each day x. ( is the day tickets go on sale).
a. Does the graph of this equation open up or down? How did you determine this?
It opens down because the x^2 term is a negative.
b. Describe what happens to the tickets sales as time passes.
Over time the sales rise, peak then begin to fall.
c. Use the quadratic equation to determine the last day that tickets will be sold.
The last day of ticket sales will be on the 60.9th(61ST)day after going on sale
Note. Write your answer in terms of the number of days after ticket sales begin.
d. Will tickets peak or be at a low during the middle of the sale? How do you know?
The ticket sales will peak during the middle of the sale.
e. After how many days will the peak or low occur?
The peak occurs on the 30th day of sales.
f. How many tickets will be sold on the day when the peak or low occurs?
g. What is the point of the vertex? How does this number relate to your answers in parts e. and f?
h. How many solutions are there to the equation ? How do you know?
i. What do the solutions represent? Is there a solution that does not make sense? If so, in what ways does the solution not make sense?
1 solutions
Answer 210065 by richwmiller(9135) on 2010-04-09 12:07:02 (Show Source):
You can put this solution on YOUR website!I already answered all but f.
f)For that just plug in x=30 and solve
g)That will be the other part of the vertex
h) told you two
I)remember I told you that they sold tickets before they started to sell tickets.
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Graphs/290283: I am getting ready to take the praxis I math test, and I am strugging with questions about graphing inequalities like this one: y=x^-2x. would you explain how to graph this one and if you have another example too please. My email: pierceluisa@yahoo.com thank you
Luisa Pierce 1 solutions
Answer 210062 by richwmiller(9135) on 2010-04-09 11:59:57 (Show Source):
You can put this solution on YOUR website!We have a problem with your problem. It is not an inequality.
Inequalities use > and <
But one way to graph an inequality is to change from < and > to equal and graph it and then decide if the line of the equation is included or not above or below or inside or outside
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Sequences-and-series/290287: 1)Frances has paints in 4 different colors, She is going to paint the inside of a box with one color and the outside of the box with another color, in how many ways can she paint the box?
I GOT 30 WAYS, but I'm not sure!
1 solutions
Answer 210059 by richwmiller(9135) on 2010-04-09 11:54:24 (Show Source):
You can put this solution on YOUR website!4*3
She can choose 4 different colors outside and the inside can't be one of them
so she has 3 choices inside
12 choices total
How did you get 30?
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Graphs/290279: Hi. I need help with writing the following equation in y=mx+b form, with slope
-1/2 and y-intercept 11. Thanks. 1 solutions
Answer 210051 by richwmiller(9135) on 2010-04-09 11:24:10 (Show Source):
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Quadratic_Equations/289684: I do not understand how to figure the solution to the equation:
x^2 + x + sqrt x^2 +x -2 = 0. I was hoping you would be able to help me understand this a little more. 1 solutions
Answer 210050 by richwmiller(9135) on 2010-04-09 11:22:06 (Show Source):
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Angles/290254: In trinagle ABC, angles A & B have the same measure, while the measure of C is 75 degrees larger than each of A & B. What are the measures of the 3 angles? 1 solutions
Answer 210044 by richwmiller(9135) on 2010-04-09 10:41:49 (Show Source):
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Travel_Word_Problems/290262: trains a and b are traveling in the same direction on parallel tracks. Train A is traveling at 60 MPH and train B is traveling at 80 MPH. Train A passes a staion at 4:10PM. If train B passes that same station at 4:22PM, at what time will train B catch up with Train A?
Exact time am or pm 1 solutions
Answer 210040 by richwmiller(9135) on 2010-04-09 10:28:43 (Show Source):
You can put this solution on YOUR website!60*1/5=12 miles
80=60=20
20*x=12
x=12/20=6/10
6/10*60=36 minutes
4:22+0:36=4:58 pm
or this way
60*(t+1/5)=80*t
60t+12=80t
12=20t
12/20=t
6/10=t
6/10*60=36 minutes=t
4:22+0;36=4:58 pm
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Probability-and-statistics/290261: Mark has 10 red marbles and 15 blue in a bag. He reaches into choses one without looking and sets it aside. He draws another. what is the probabiliy that he draws 2 blue marbles. What is the %? 1 solutions
Answer 210039 by richwmiller(9135) on 2010-04-09 10:22:44 (Show Source):
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Miscellaneous_Word_Problems/290257: Can use some help with a word problem. This is what it is:
A biologist recorded 2 snakes on 9 acres in one area and 9 snakes on 12 acres in another are. Let s be the number of snake and a be the number of acres. Find a linear equation that you could use to calculate for any number of acres.
I tried to put the numbers in the formula of y=mx+b (2,9)and (9,12).
I solved for m and got -3/7, but I know I am doing something wrong because we have choices as:
a)s=7a b)3s=-2a+9 c)3s-7a-57 d)3s-7a
I do not know what I am doing wrong because my final answer was y=6/7+b.
1 solutions
Answer 210035 by richwmiller(9135) on 2010-04-09 10:14:10 (Show Source):
You can put this solution on YOUR website!First you have the x and y backwards.
x (a) is acres and y (s) is snakes
(9,2) and (12, 9)
so s=ma+b
But first we have to find the slope
(y-y)/(x-x)=m
or in this case
(s-s)/(a-a)=m
(9-2)/(12-9)=7/3=m
7/3=m
s=(7/3)*a+b
now plug in either point
2=(7/3)*9+b
2=63/3+b
2=21+b
-19=b
s=7a/3-19
3s=7a-57
The closest answer is c
3s-7a-57
I think you copied - for =
Double check your answer options
Perhaps you copied them wrong.
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Quadratic_Equations/290255: Dear tutor, I am in Iraq about to fail my math class. Can you please assist with these problems?
Suppose you are an event coordinator for a large performance theater. One of the hottest new Broadway musicals has started to tour and your city is the first stop on the tour. You need to supply information about projected ticket sales to the box office manager. The box office manager uses this information to anticipate staffing needs until the tickets sell out. You provide the manager with a quadratic equation that models the expected number of ticket sales for each day x. (x = 1 is the day tickets go on sale).
tickets = -0.2^2 + 12x + 11
In this equation, does the graph of the equation open up or down?
Describe what happens to the tickets sales as time passes?
Use the quadratic equation to determine the last day that tickets will be sold.
Note. Write your answer in terms of the number of days after ticket sales begin.
After how many days will the peak or low occur?
1 solutions
Answer 210030 by richwmiller(9135) on 2010-04-09 09:56:34 (Show Source):
You can put this solution on YOUR website!You forgot the x^2 in the first term which caused this equation to be a straight line rather than a parabola.
t= -0.2x^2 + 12x + 11
opens down - Notice the x^2 term is minus
This is a parabola like the St Louis Arch .
It rises then peaks and falls
The graph below doesn't show the arch because the numbers shown are too small
| Solved by pluggable solver: SOLVE quadratic equation with variable |
Quadratic equation (in our case ) has the following solutons:

For these solutions to exist, the discriminant should not be a negative number.
First, we need to compute the discriminant : .
Discriminant d=152.8 is greater than zero. That means that there are two solutions: .


Quadratic expression can be factored:

Again, the answer is: -0.903074280724887, 60.9030742807249.
Here's your graph:
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The solutions tells when t is zero.
The peak will be -b/2a=-12/-2*.2=120/4=30
-b/2a is the x of the vertex and the axis of symmetry.
The peak occurs on the 30th day.
The last day is 60.9 or on the 61st day
And apparently some tickets were sold the day before tickets were sold.
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Sequences-and-series/289472: Which sequence follows the rule 6n-2, where n represents the position in the sequence?
a. 6, 12, 18, 24
b. 4, 10, 16, 22
c. 4, 12, 16, 24
d. 4, 12, 18, 22
1 solutions
Answer 210026 by richwmiller(9135) on 2010-04-09 09:29:26 (Show Source):
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Problems-with-consecutive-odd-even-integers/290166: The sum of two numbers is 32; the larger number is 12 greater than twice the smaller. What are the 2 numbers? 1 solutions
Answer 210016 by richwmiller(9135) on 2010-04-09 07:21:54 (Show Source):
You can put this solution on YOUR website!10 and 22 don't work
because the 22 is not 12 greater than twice the smaller
it is only 12 greater than the smaller.
32-12=20
20/3=smaller
and 40/3+12= larger
6 2/3
12 4/3=13 1/3+12=25 /13
25 1/3+6 2/3=32
check
25 1/3-12=13 1/3
13 1/3 is twice 6 2/3
ok
Answer
25 1/3
6 2/3
which is equal to maththerapy's answer since
20/3=6 2/3
76/3=25 1/3
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Word_Problems_With_Coins/290168: Ann, Ben, and Carol have some money. If Ann gives Ben 30 cents, then Ben will have twice as much as Ann. If Ben givens Carol 30 cents, then Carol will have as much as Ben. If Carol gives Ann 15 cents, they will both have the same amount of money. How much money to they each have? 1 solutions
Answer 210014 by richwmiller(9135) on 2010-04-09 06:55:42 (Show Source):
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Pythagorean-theorem/290201: A portable ladder is needed to climb onto a rooftop 24 feet high. How long should the ladder be? How far should its base set away from the building wall? Explain your answer and show your calculation. 1 solutions
Answer 210013 by richwmiller(9135) on 2010-04-09 06:38:29 (Show Source):
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Miscellaneous_Word_Problems/290210: In an archery competition, Galen hits the bullseye three times as often as Jason. Jason hits it four times fewer than Kevin and Eddy hits it one less than twice the number of times that Kevin does. Nathalie hits the bullseye as many times as Jason and Galen combined. If Kevin hits the bullseye 9 times, how many times was the bullseye hit?
(A)24 (B) 42 (C) 54 (D) 60 (E) 66
1 solutions
Answer 210009 by richwmiller(9135) on 2010-04-09 05:56:05 (Show Source):
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Coordinate-system/290214: How far from the origin is the line 3x + 4y = 100?
(a)20 (b) 21 (c) 22 (d) 23 (e) None of the above
1 solutions
Answer 210007 by richwmiller(9135) on 2010-04-09 05:47:02 (Show Source):
You can put this solution on YOUR website!4 steps
a)find the slope of he given line.
b)find a line perpendicular
c)Find a point with the new slope (intersection of two lines)
d) Find distance between two points.
e) answer question
a)3x+4y=100
-a/b=-3/4
so we want 4/3
b)y=mx+b
0=0+b
b=0
c)y=4x/3
4y=100-3x
y=-3x/4+100
y=4x/3
4x/3=-3x/4+100
14x=-9x+1200
25x=1200
x=1200/25=48
x=48
y=4x/3
y=16*3*4*x/3
y=64
d)64^2+48^2=d^2
d=80
e)Answer none of the above
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Linear_Equations_And_Systems_Word_Problems/290176: A shopkeeper has two types of coffee beans on hand. One type sells for $3.20 per lb, the other for $7.80 per lb. How many pounds of the $3.20 per lb coffee beans must be used in the mixture to produce 80 lbs of a blend that sells for $5.04 per lb?
Round your answer to 2 decimal places.
1 solutions
Answer 209989 by richwmiller(9135) on 2010-04-08 22:59:34 (Show Source):
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Mixture_Word_Problems/290177: I have 2 problems, hear they are.
A gallon of vinegar is labelled 5% acidity. How many fluid Ounces of pure acid must be added to get 6% acidity?
1 solutions
Answer 209988 by richwmiller(9135) on 2010-04-08 22:51:12 (Show Source):
You can put this solution on YOUR website!Guess what? This website has rules. "Hear" are some of them.
One problem at a time.
No similar problems.
Limit 4 problems daily.
(128*.05)+x=.06*(x+128)
x=1.3617
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