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Question 582187: The profit P, in dollars, gained by selling x computers is modeled by the equation P= -5x^2 + 1000x + 5000. Find the number of computers that must be sold to obtain a profit of $55,000.00?
Using the quadratic equation, I came up with the computer cost being $41.42 then divided $55,000 by that and came out with 1327.86 computers needed to be sold to obtain that profit of $55,000.
Please help.
Diana
Click here to see answer by stanbon(57361)

Question 582586: How many and of what type are the solutions of a quadratic equation when the value of the radicand is -20
Click here to see answer by jim_thompson5910(28595)

Question 582589: Where does the graph of y = 2x^2 − x − 3 cross the x-axis?
A. (−, 0) and (3, 0)
B. (, 0) and (−3, 0)
C. (−, 0) and (1, 0)
D. (, 0) and (−1, 0)
Click here to see answer by jim_thompson5910(28595)

Question 582617: Determine whether the graph of y = x^2 − 6x + 3 has a maximum or minimum point, then find the maximum or minimum value.
Click here to see answer by stanbon(57361)

Question 582722: ou drop a pencil out of a window that is 2o ft above the ground. Use the formula V squared = 64s, where V is the speed and s is the distance fallen, to calculate the speed the pencil is traveling when it hits the ground.
Click here to see answer by josmiceli(9681)

Question 582875: When using the quadratic formula to solve a quadratic equation in the form of ax^2 + bx + c, explain what would happen to b^2 when it is less than 4ac and 4ac is positive
Click here to see answer by jim_thompson5910(28595)

Question 583152: how do i figure out a quadratic equation.
Click here to see answer by solver91311(16897)

Question 583145: My paper says: Find the value of the discriminant for 9x^2+1=6x. Then describe the number and type of roots for the equation..... I already found the discriminant to be -72 i just dont know how to do the last part
Click here to see answer by solver91311(16897)

Question 583502: PLEASE help me with this challenging problem!!!
An indoor track is made up of a rectangular region with two semi-circles at the ends. The distance around the track is to be 400 meters. Determine the radius of the semicircular ends of the track in terms of y.Use the result to write and equation in terms of x and y for the distance around the track. Use your result from that to write the area A of the rectangular section as function of x.What dimensions for the rectangular region maximize the area (of the rectangular region)? Do not attempt to maximize the area for the whole figure!!
Click here to see answer by Alan3354(30993)

Question 583585: The product of 2 positive integers is 64. One is 4 times the other. Find the integers.
Click here to see answer by JBarnum(2044)

Question 583740: The manager of a peach orchard is trying to decide when to arrange for picking the peaches. If they are picked now, the average yield per tree will be 100 pounds, which can be sold for $.40 per pound. However, past experience shows that if the manager postpones the harvest a bit, the yield per tree will increase by about 5 pounds per week but the price will decrease about $.02 per pound per week.
a) Construct a function which gives the revenue per peach tree. Be sure to state what your variables represent.
Click here to see answer by ankor@dixie-net.com(15656)

Question 584022: 12x^2-10x-42=0
I have to solve this quadratic equation two different ways and I need to show my work and explain what I am doing. I have no clue where to even start. I didn't even know there was two ways to solve this.....Any help please?
Click here to see answer by KMST(1868)

Question 584703: factor x squared - 81
Click here to see answer by mananth(12270)

Question 584725: can you please answer this problem? Joey is 9 years older than Marivic. Six years ago, the product of their ages is 190. Find their present ages.
I hope to hear you soon. thank you!
Click here to see answer by JBarnum(2044)

Question 584735: THE DIFFERENCE OF SQUARE OF TWO NUMBER IS 180 .THE SQUARE OF THE SMALLER NUMBER IS 8 TIMES THE LARGER NUMBER .FIND THE TWO NUMBERS?
Click here to see answer by ankor@dixie-net.com(15656)

Question 584968: write each quadratic equation in standard form.
1. y=3(x+2)squared-10 2.y= -(x+4)squared-1 3.y=(x-5)squared+2
my question is how do i solve these
sorry about the "squared" i didnt know how to put the 2 up in the corner-- in squared form..
Click here to see answer by ankor@dixie-net.com(15656)

Question 585004: In questions 6-9, use the discriminant to determine the number of solutions of the quadratic equation, and whether the solutions are real or complex. Note: It is not necessary to find the roots; just determine the number and types of solutions.
The above is the instructions for the problems. Below I have worked out each math problem, but once again, I'm not sure whether or not the solutions I have are real or complex. I think I worked each problem out correctly. If I have not please let me know. If I have, I guess the only thing I need clarifying on is if the solution I have is real or complex.
6. x²+6x-7=0
Use the quadratic formula to find the solutions.
X=-b±√b²-4ac ax²+bx+c=0
2a
A=1, B=6, C=-7
b²-4ac The discriminant of a quadratic is the expression inside the radical of the quadratic formula.
((6)²-4(1)(-7)) Substitute in the values of a,b, and c.
36-4(1)(-7) Squared 6
36-4(-7) Multiplied 1 by -7
36+28 Multiplied -4 by each term inside the parenthesis.
64 Added 36+28
ANSWER: 64 Real or complex????

7.z²+z+1=0
Use the quadratic formula to find the solutions.
X=-b±√b²-4ac ax²+bx+c=0
2a
A=1, B=1, C=1
b²-4ac The discriminant formula
((1)²-4(1)(1)) Substitute in the values of a,b, and c
1-4(1)(1) Expand the exponent 2 to the expression
1-4(1) Multiply 1*1
1-4 Multiply -4 by each term inside the parenthesis
-3 Subtract 4 from 1
ANSWER: -3 Real or complex??

8. (3)½y²-4y-7(3)^½=0
√(3)*y²-4y-7(3)^½=0 An expression with a fractional exponent can be written as a radical with an index equal to the denominator of the exponent
√3*y²-4y-7(3)^½=0 Removed the parenthesis around the expression 3
√3*y²-4y+(-7*√(3))=0 Reduced
√3*y²-4y+(-7*√3)=0 Removed the parenthesis around the expression 3
√3*y²-4y+(7√3)=0 Multiplied -7 by √
y²√3-4y-7√3=0 Multiplied √3 by y²
Y=-b±√b²-4ac ay²+bx+c=0
2a
A=√3, B=-4, C=-7√3
b²-4ac Discriminant formula
((-4)²-4(√3)(-7√3)) Substitute in the values of a,b,c
(4)(-4)-4(√3)(-7√3) Squared
16-4(√3)(-7√3) Multiply to simplify the expression (-4)(-4)
16-4(-7√3²) Multiply -7W to get -7W²
16+28√3² Multiplied -4 by each term inside the parenthesis.
16+28(3) Squared
16+84 Multiplied 28 by each term inside the parenthesis.
ANSWER: 100 Real or complex???

9. 2x²-10x+25=0
X=-b±√b²-4ac ax²+bx+c=0
2a
A=2, B=-10, C=25
b²-4ac
((-10)²-4(2)(25)) Substitute in the values of a,b, and c.
(-10)(-10)-4(2)(25) Squared
100-4(2)(25) Multiplied to simplify the expression (-10)(-10)
100-4(50) Multiplied 2 by25
100-200 Multiplied -4 by each term inside the parenthesis.
ANSWER: -100 real or complex??

Click here to see answer by jim_thompson5910(28595)

Question 585018: c) Calculate the value of if the difference between the roots of x^2-6x+k=0
is 3.

Click here to see answer by jim_thompson5910(28595)

Question 584986: Suppose a particular star is projected from an aerial firework at a stating height of 520 ft with an initial upward velocity off 72ft/s. How long will it take for the star to reach its maximum height? How far will it be?
The equation is h= -16t^2+ 72t +520
also, describe the importance of quadratics (one paragraph) and how quadratics helps people to understand something in the real world
Click here to see answer by ankor@dixie-net.com(15656)

Question 585020: given that a root is two times the other root of the quadratic equation 4x^2-18x=k=0.
find the value of k
Click here to see answer by ankor@dixie-net.com(15656)

Question 585100: 6 ( ln l -3) - 4l n l +5 = 11
Click here to see answer by Alan3354(30993)

Question 585163: A small painting has an area of 400 cm 2 . The length is 4 more than 2 times the width. Find the dimensions of the painting. Solve by completing the square. Round answers to the nearest tenth of a centimeter.
Click here to see answer by josmiceli(9681)

Question 584959: OK, first of all the problem that I need help with is P(x)=-x^2+110x-1,000. P being 5, 50, and 120. I think that if I can get help answering the five then I should be able to figure out the 50 and the 120 (I hope). I am going to college and totally lost so if you could help me with this problem I would greatly appreciate it. I also have to graph it when I am done, but like I said earlier if I can figure out the answer to P(x)=-x^2+110x-1,000 with P being 5 I should be able to get the rest.
Click here to see answer by scott8148(6628)

Question 585170: x² - 2x -35=0 solve each equation by competing the sqaure
Click here to see answer by ankor@dixie-net.com(15656)

Question 585215: An airplane has a total of 152 seats. The number of coach-class seats is five more than six times the number of first-class seats. How many of each type of seat are there on the plane? Write two equations using c to represent coach-class seats and f to represent first-class seats. Solve using elimination or substitution
Click here to see answer by mananth(12270)

Question 585217: solve using the quadratic formula
1) 9x^2+10x-13=0

2) 5y^2-8y=2

Thanks
Click here to see answer by jim_thompson5910(28595)

Question 585401: which is the standard to H=-16t^2+vt+s
Click here to see answer by stanbon(57361)

Question 585432: ????
The Travel Time bus company has determined that when x tourists are given a particular bus
tour, the profit P is given by
P(x) = –0.25 x2 + 29.50x – 170
(a) What is the company’s profit if 42 tourists are given the tour?
(b) How many tourists should be given the tour in order to maximize the company’s profit?
Click here to see answer by nerdybill(6960)

Question 585708: i have a question my teacher taught me to do these equations using -b over 2a the putting the product i got from that into the regular Ax+Bx+C=y equation then i would take whatever i got from tose two eqautions and graph them with the y-intercept my question is how do no if it shifts from left to right and how do i deal with fractions in these
Click here to see answer by richwmiller(9143)

Question 586056: How do you find the vertex of this equation? x^2+3x-4?
Click here to see answer by jim_thompson5910(28595)

Question 585577: Please help I am having real trouble with this. Thank you!!!!
Ticket Sales
Living in or near a metropolitan area has some advantages. Entertainment opportunities are almost endless in a major city. Events occur almost every night, from sporting events to the symphony. Tickets to these events are not available long and can often be modeled by quadratic equations.
Application Practice
Answer the following questions. Use Equation Editor to write mathematical expressions and equations. First, save this file to your hard drive by selecting Save As from the File menu. Click the white space below each question to maintain proper formatting.
1. 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).
Tickets = -x^2 + 5x + 29 = 0

a. Does the graph of this equation open up or down? How did you determine this?

b. Describe what happens to the tickets sales as time passes.
c. 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.

d. Will tickets peak or be at a low during the middle of the sale? How do you know?

e. After how many days will the peak or low occur?

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 -x^2 + 5x + 29 = 0? 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?

Click here to see answer by KMST(1868)

Question 586812: how do you find the values of 'a, b and c when given the following points on the graph (0;3) , (-3;0) and (1;0)
Click here to see answer by solver91311(16897)

Question 586814: 8x + 2 = -4x2
Will the graph of the equation above intersect the x-axis in zero, one, or two points?
(Use the quadratic formula to help you answer this question.)

A) one
B)two
C)There is not enough information.
D) zero

2.2x2 + 4x = -2
Will the graph of the equation above intersect the x-axis in zero, one, or two points?
(Use the quadratic formula to help you answer this question.)

A) zero
C) There is not enough information.
C) one
D) two

Click here to see answer by solver91311(16897)

Question 586833: hi i really need someone to solve it fast (2x-1)^2 - (x-4)^2 + 12x - 60 = 0
i know the answer is x = 5/-5 but i need to know how .
thanks !!!
Click here to see answer by scott8148(6628)

Question 586897: Solve.
12(x-4)-(x+2)=(x+2)(x-4)
They book has the answer of 7 and 6.
Can you tell me how they got this answer?
I came up with x = 13 and 208.
Click here to see answer by Edwin McCravy(8909)

Question 586935: Hello, I need to write an equation with the given roots, write the equation in the form ax^2 + bx + c = 0. The problem is 3, -4.
Click here to see answer by richwmiller(9143)

Question 586931: a rectangular pond is to be constructed in a park. the pond will be 5 feet by 7 feet and is to be surrounded by a sidewalk of x feet. the gardener is interested in the area the pond and sidewalk will encompass. write a representative function for the area of this region as a function of x. what kind of function is this?
Click here to see answer by richwmiller(9143)

Question 587072: solve 4(x-2)^2=36 by using square roots.
Click here to see answer by lwsshak3(6509)

Question 587081: Can you exlain the steps to find the answer of:
64=x^2+12x
Click here to see answer by algebrahouse.com(1079)

Question 587112: Solve:
3x^2=13x-4
Click here to see answer by xdragonfight(116)

Question 587121: Solve:
1=3x^2+2x
Click here to see answer by xdragonfight(116)

Question 587211: use the height as a function of time in motion equation: h(t) = -16t squared + vt + c A baseball player hits a pitched ball when it is 4 ft above ground. The initial upward velocity is 80 ft/sec. How long will it take for the ball to hit the ground?
Click here to see answer by ankor@dixie-net.com(15656)

Question 587320: 3p+2y=209
p+y=81
This would be correct right?
3p+2y=209
p=-y+81
Then,
3(-y+81)+2y=209
-3y+243+2y=209
Then,
-y=-34
y=34
So, don't you enter y into the equation? Like this,
p=-y+81
p=-34+81
p=47
So.
y=34 and p=47
My teacher says that this is wrong?
Click here to see answer by stanbon(57361)

Older solutions: 1..45, 46..90, 91..135, 136..180, 181..225, 226..270, 271..315, 316..360, 361..405, 406..450, 451..495, 496..540, 541..585, 586..630, 631..675, 676..720, 721..765, 766..810, 811..855, 856..900, 901..945, 946..990, 991..1035, 1036..1080, 1081..1125, 1126..1170, 1171..1215, 1216..1260, 1261..1305, 1306..1350, 1351..1395, 1396..1440, 1441..1485, 1486..1530, 1531..1575, 1576..1620, 1621..1665, 1666..1710, 1711..1755, 1756..1800, 1801..1845, 1846..1890, 1891..1935, 1936..1980, 1981..2025, 2026..2070, 2071..2115, 2116..2160, 2161..2205, 2206..2250, 2251..2295, 2296..2340, 2341..2385, 2386..2430, 2431..2475, 2476..2520, 2521..2565, 2566..2610, 2611..2655, 2656..2700, 2701..2745, 2746..2790, 2791..2835, 2836..2880, 2881..2925, 2926..2970, 2971..3015, 3016..3060, 3061..3105, 3106..3150, 3151..3195, 3196..3240, 3241..3285, 3286..3330, 3331..3375, 3376..3420, 3421..3465, 3466..3510, 3511..3555, 3556..3600, 3601..3645, 3646..3690, 3691..3735, 3736..3780, 3781..3825, 3826..3870, 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