Tutors Answer Your Questions about Quadratic Equations (FREE)
Question 149716: The rate at which a tablet of vitamin C begins to dissolve depends on the surface area of the tablet. One brand of tablet is 2 centimeters long and is in the shape of a cylinder with hemispheres of diameter 0.5 centimeter attached to both ends. A second brand of tablet is to be manufactured in the shape of a right circular cylinder of altitude 0.5 centimeter.
a) Find the diameter of the second tablet so that its surface are is equal to that of the first tablet.
b) Find the volume of each tablet.
Click here to see answer by ankor@dixie-net.com(15652)   |
Question 149906: If a soccer ball is kicked straight up from the ground with an initial velocity of 32 feet per second, then its height above the earth in feet is given by s(t) = -16t^2 + 32t, where t is time in seconds. What is the maximum height reached by the ball? Graph parabola 0<=t<=2
Click here to see answer by jim_thompson5910(28595) |
Question 149912: The stabilization ratio (birth/death)for south and central america can be modeled by the formula y= -0.0012x^2 + 0.074x + 2.69 where y is the number of birth divided by the number of deaths in the year 1950 + x.
Use the formula to find the year in which the stabilization ratio was at its maximum?
What was the maximum stabilization ration from above?
What is the significance of a stabilization ratio of 1?
Click here to see answer by ankor@dixie-net.com(15652) |
Question 149908: A company uses the formula C(x)= 0.02x^2-3.4x + 150 to model the unit cost in dollars for producing x stabilizer bars. For what number of bars is the unit cost at its minimum? What is the unit cost at that level of production?
Click here to see answer by Alan3354(30993)  |
Question 149857: I know (think) I did this right but does seem right.
6x^2+17x-40 + 3 - 5x
___________ ___ ______
x^2+x-20 x-4 x+5
This is what i did...
6x^2+17x-40 +3 -5x
___________ ____ _____
(x-4)(x+5) x-4 x+5
6x^2+17x-40 + 3(x+5) - 5x(x-4)
_____________________________________
(x-4)(x+5)
6x^2+17x-40 +3x+15-5x^2+20x = (6x^2-5x^2)+(17x+3x+20x)+(-40+15)= x^2+40x-25
x^2+40x-25
__________
(x-4)(x+5)
I don't see a way to break it down any further...?
Click here to see answer by ankor@dixie-net.com(15652) |
Question 150123: 3x^2+19x-14=0 then I have to write it in the quadratic formula. -19+-sqrt(-19^2-4*3*-14/2*19; x=19+sqrt361+168/38; 19+-sqrt529/38; x=19+-23/38; x=42/38=6/2; x=6/2=-4 I got the -4 sub 19 from 23 to get the -4. Can you please tell me if this is right because there is alot of steps to this thank you.
Click here to see answer by Fombitz(13828)  |
Question 150370: Please help. If a rock is thrown upward with an initial velocity of 40 feet per second from the top of a 30 foot building how high is the rock after 2 seconds,how many seconds will the graph reach maximum height and what is the maximum height? Can someone please help
Click here to see answer by Earlsdon(6287) |
Question 150442: The following appears to prove that any two numbers are equal. Obviously it is wrong; can you spot the flaw?
Let a and b be any two different numbers. Define x as the difference between them:
x = b - a
Multiply both sides of the equation by (b-a):
x(b – a) = (b – a)(b – a)
bx – ax = b^2 – 2ab + a^2
Add –bx+ab-a^2 to both sides and simplify:
bx – ax – bx + ab – a^2 = b^2 – 2ab + a^2 – bx + ab – a^2
bx – bx – ax + ab – a^2 = –bx + b^2 – 2ab + ab + a^2 – a^2
–ax + ab – a^2 = –bx + b^2 – ab
Both sides of this equation have a common factor:
a(–x + b – a) = b(–x + b – a)
Divide both sides by (-x+b-a):
a(–x + b – a)/-x + b-a = b(–x + b – a)/ -x + b - a
a = b
What was my mistake?
Click here to see answer by vleith(2825) |
Question 150441: The following appears to prove that any two numbers are equal. Obviously it is wrong; can you spot the flaw?
Let a and b be any two different numbers. Define x as the difference between them:
x = b - a
Multiply both sides of the equation by (b-a):
x(b – a) = (b – a)(b – a)
bx – ax = b^2 – 2ab + a^2
Add –bx+ab-a^2 to both sides and simplify:
bx – ax – bx + ab – a^2 = b^2 – 2ab + a^2 – bx + ab – a^2
bx – bx – ax + ab – a^2 = –bx + b^2 – 2ab + ab + a^2 – a^2
–ax + ab – a^2 = –bx + b^2 – ab
Both sides of this equation have a common factor:
a(–x + b – a) = b(–x + b – a)
Divide both sides by (-x+b-a):
a(–x + b – a)/-x + b-a = b(–x + b – a)/ -x + b - a
a = b
What was my mistake?
Click here to see answer by Edwin McCravy(8909)  |
Question 150456: My father-in-law used to have a garden in our backyard. We worried about him weeding the whole garden by himself so we usually sent one of our children out to help. Now, if my son worked on the garden by himself it would take him 4 hours longer to weed the garden than his grandfather took. However, if he worked with my father-in-law, he worked twice as fast. The formula
t(t+4)/3t+4 represents how long it took for both of them to weed the whole garden working together.
Using the formula t(t+4)/3t+4, How long would it take the son alone,if it took an hour and a quarter for them to weed the garden together?
Please help?
Click here to see answer by stanbon(57347) |
Question 150318: The path of a falling object is given by the function s+-16t^2+vot + so where represents the initial velocity in ft/sec and represents the initial height in feet. Also, s o represents the height in feet of the object at any time, t, which is measured in seconds.
a) If a rock is thrown upward with an initial velocity of 40 feet per second from the top of a 30-foot building, write the height (s) equation using this information.
Click here to see answer by ankor@dixie-net.com(15652) |
Question 150584: 1. The square of an interger is 30 more than the integer. Find the integer.
I tried.... x^2 = x+30 to get a solution of x=6 and x-5
I am unsure if this is the right equation for the problem above.
2. The sum of an integer and its square is 30. Find the number.
I tried..... x + x^2= 30 to get a solution of x=-6 and x=5
Once again I am unsure if this is the right equation for the problem above.
Click here to see answer by Edwin McCravy(8909) |
Question 150601: I really need help with this 4 part equation.I have looked at it and just stumped could someone please help me.
A.Without solving the equation or factoring , determine the solutions to the equation x^2-2x-8=0 by inspecting the graph. why?
B. Does the function have a maximum or a minimum?
C. What is the eqution of the line of symmetry for this graph?
D. What are the coordinates of the vertex in (x,y)form?
Click here to see answer by josmiceli(9678)  |
Question 150618: Please show me how to work out this problem. I know the roots are -1/3, -1/2, and 3, but I don't know how to work the problem by hand to find the answer. Please help so I know how to solve this kind of problem in the future!
-21x^3 + 53x^2 + 53x + 20 = 3x^3 + x^2 -3x + 8
-24x^3 + 52x^2 + 56x + 12 = 0
Click here to see answer by Edwin McCravy(8909) |
Question 150596: y=x^2+2x-15 find the corresponding y values for x=-4,-3,-2,-1,0,1,2 y=4x^2 +2x-15 y=18x-15 y=18x-15 then moved the 18 xon the other side to move the x to the other side y=15-18x the answer is -3 is this right. Then how do i find the corresponding for the # that is at the top.
Click here to see answer by jim_thompson5910(28595) |
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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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11161..11205, 11206..11250, 11251..11295, 11296..11340, 11341..11385, 11386..11430, 11431..11475, 11476..11520, 11521..11565, 11566..11610, 11611..11655, 11656..11700, 11701..11745, 11746..11790, 11791..11835, 11836..11880, 11881..11925, 11926..11970, 11971..12015, 12016..12060, 12061..12105, 12106..12150, 12151..12195, 12196..12240, 12241..12285, 12286..12330, 12331..12375, 12376..12420, 12421..12465, 12466..12510, 12511..12555, 12556..12600, 12601..12645, 12646..12690, 12691..12735, 12736..12780, 12781..12825, 12826..12870, 12871..12915, 12916..12960, 12961..13005, 13006..13050, 13051..13095, 13096..13140, 13141..13185, 13186..13230, 13231..13275, 13276..13320, 13321..13365, 13366..13410, 13411..13455, 13456..13500, 13501..13545, 13546..13590, 13591..13635, 13636..13680, 13681..13725, 13726..13770, 13771..13815, 13816..13860, 13861..13905, 13906..13950, 13951..13995, 13996..14040, 14041..14085, 14086..14130, 14131..14175, 14176..14220, 14221..14265, 14266..14310, 14311..14355, 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