Questions on Algebra: Quadratic Equation answered by real tutors!

Tutors Answer Your Questions about Quadratic Equations (FREE)

Question 129635: What is the inverse of the function y=logbase2 x?
Click here to see answer by edjones(8007)

Question 129639: Solve for x:
(x+3)^2/3=4
Click here to see answer by edjones(8007)

Question 129633: Which equation best models the data:
x: -2, 0, 2, 4
y: 3.5, 7, 14, 28
a)y=3.5(2)(^x/2)
b)y=3.5(2)^x
c)y=7(2)(^x/2)
d)y=7(2)^x
Click here to see answer by edjones(8007)

Question 129723: I have some problems I got wrong on my test. Please explain step by step what I should have done. I am allowed four, so here they are.

1.) Pizza Unlimited has the following prices for pizzas. Price is related to diameter by a quadratic equation. Fit a quadratic equation into the data points (8, 3.39), (12, 5.12), and (16, 7.29).
Diameter Price
8 inch $3.39
12 inch $5.12
16 inch $7.29
A.) Price =what quadratic equation?
B.) Using the equation find the price of a 14 inch pizza.
I know the answers, but I did the problem wrong, will you please show me the steps? How did they get the equation?
Answer A: 0.01375x^2 +0.1575x+1.25
Answer B: 14 inch pizza costs $ 6.15

2.) Solve for x. (x-6)^2 + (x+1)^2 = 0
The solutions are 5 + 7 i /2, 5-7 i/2
How do I know when to place the � I � one there?
Please show the step by step way to get this solution.

3.) What is the maximum product of two numbers whose sum is -6? What numbers yield this product? The max product is?
I put the max product at 9 (incorrect) and the numbers yielding this product at -3, -3 (correct)
However when I did the same problem with -16 instead of -6, I got 49 for the max product and it was correct. I thought the max product was the number in question squared. How do I get the max product?

4.) Solve the formula for the given number. Assume all variables represent positive numbers.
(N=n^2 � 19 n)/6; for n
I got n = (19 + sqrt sign 361 + 36 N)/2 (incorrect)
The answer is n = (19 + sqrt sign 361 + 24 N)/2
What did I do wrong, please show me the steps.
Thanks for all your help!!!!!!!!!! :o)

Click here to see answer by chitra(359)

Question 129818: can you assist me to solved this linear equation by graphing
x+2y=5
x-y=2
how do I determin wheather the following has one solution, no solution or many solution. : y=-x+2
3x+3y=6
use substitution to solved: 2x+y=7
5x-2y=7
Thank you for your assistant
Click here to see answer by solver91311(24713)

Question 129565: Michael purchased a Wayne Gretzkey rookie card for $3.50 in 1985. In 2008 the card is worth $58.19. What is the annual rate of appreciation??? I think it is 1.3%. Can someone please help me ???
Click here to see answer by scott8148(6628)

Question 129853: What is the domain for y=logbase2(3x-6)?
Is it :
a)x is greater than 0
b)x is greater than or equal to 0
c)x is greater than 2 OR
d)x is greater than-2
Click here to see answer by oscargut(2103)

Question 129642: use the sum and product propeties to wtie a quatraic equation whose solution is 5,6
Click here to see answer by scott8148(6628)

Question 129857: Sarah wants her $9000 GIC to double in value in nine years. What annual rate of interest is required for her to reach her goal. Assume interest is compounded annually.
Click here to see answer by stanbon(75887)

Question 129854: Which of these situations would produce an exponential graph ?
a) The pendulum on a clock moves 10cm to the right and 10cm to the left of its resting position.
b) The temperature of a hot metal rod is recorded at regular intervals after it is removed from the fire.
c) A square based prism is being filled with water at a constant rate.
d) The path of a ball as it is thrown through the air.
Click here to see answer by rapaljer(4671)

Question 129855: Solve for x:
a) (2x-1)(^1/2)=sqrt3
b) 8(^2x)+8(^x) -12=0
Click here to see answer by edjones(8007)

Question 129852: Solve:
a) log(x-2)+log(x+1)=1
b) 4(^1-x)=3*5^x
c) logbase2(1-x)+logbase2(4x+1)=0
Click here to see answer by edjones(8007)

Question 129850: Michael purchased a Wayne Gretzkey rookie card for $3.50 in 1985. In 2008 the card is worth $58.19. What was the annual rate of appreciation ?
I think the answer is 1.3% ????
Click here to see answer by oscargut(2103)

Question 129899:
The length of a rectangle is 5 less than twice the width. The area of the rectangle is 7 square units. Find the dimensions of the rectangle. Hint: quadratic formula!
my work so far: 2w-5=L w(2w-5)=7

w(2w)-5w-7=0

Click here to see answer by checkley71(8403)

Question 129969: how to factor quadratic equation: 5X^2 + 25X + 5= 0
Click here to see answer by jim_thompson5910(35256)

Question 129536: 2x-1 = x+1
____ ____
4x+3 3x+2
They're fractions 2x-1 over 4x+3 is equal to x+1 over 3x+2
And i cant figure out what im supposed to do
Click here to see answer by scott8148(6628)

Question 129568: What is the domain for y=logbase2(3x-6)??? I think it is (x such that x is greater than 0, x belongs to a set of real numbers). Can anyone clarify ????
Click here to see answer by scott8148(6628)

Question 129571: Which equation best models the data:
x: -2,0,2,4
y: 3.5,7,14,28
a) y=3.5(2)(^x/2)
b) y=3.5(2)^x
c) y=7(2)^x/2
d) y=7(2)^x
I think it is (b) ?????????
Click here to see answer by scott8148(6628)

Question 129574: Solve for x:(2x-1)^1/2=sqrt3
Click here to see answer by scott8148(6628)

Question 129575: Solve for x: (x+3)^2/3=4
Click here to see answer by scott8148(6628)

Question 130013: I need help with two more problems. They do not come from a book. I know the answers but am lost on the way to do them. I have a big test tomorrow and need to understand these a little better. Will you please show me the steps? Thank you very much.

1.) Solve for x. x^2-x+4=0
Answer is �+sqrt15/2i, �-sqrt15/2i

2.) Solve (x^2-6x)^2 - 11(x^2-6x)-80=0
I think it may be let u=x^2-6x, but was not sure. The answer is 5, 1, 8, -2

Click here to see answer by scott8148(6628)

Question 130117: find a quadratic equation whose graph will fit the following points (1,2) (0,5) (-1,14)
Click here to see answer by stanbon(75887)

Question 130078: My least favorite because I do not understand these:(
What is the focal point of 1/3(y-2)=2(^-x+5)
Click here to see answer by stanbon(75887)

Question 130059: Solve for x:
(2x-1)^1/2=sqrt3
Click here to see answer by bucky(2189)

Question 130178: Solve for x: (x+3)^2/3=4
Click here to see answer by stanbon(75887)

Question 130177: What is the inverse of the function y=logbase2 x? Is it
a) y=2^-x
b) y=2^x
c) y=x^2
d) y=logbasex 2
Click here to see answer by stanbon(75887)

Question 130176: What are the coordinates of the focal point y=3(2)(^2x+4)-5 ?

Click here to see answer by stanbon(75887)

Question 130175: Solve: logbase2(1-x)+logbase2(4x+1)=0
Click here to see answer by stanbon(75887)

Question 130211: 16=1/9(x+1)^2
Click here to see answer by mayank(15)

Question 130129: The problem is found in the chapter titled Quadratic Equations, Functions, and Models and asks simply to solve: 3y^3-5y-2y=0
Click here to see answer by scott8148(6628)

Question 130272: I am supposed to "Solve each quadratic equation by completing the square. Leave your answer in radical form." I'm not really sure what the radical form is. I don't even know if this question falls under the section of quadratic equation or radicals. My textbook says I need to complete the square or something. The equation is . I tried to solve it symbollically (I think..) and I: added the 8 to the zero, square-rooted the whole thing and somehow I ended up with . I'm not sure if I'm done or not... Please help!
Click here to see answer by Earlsdon(6294)

Question 130315: To you that have answered my previous questions, thank you! They are not being mailed to me so I cannot leave a thank you note. I have two more questions before my final, if I can get help, please.

1.) Find the x-intercepts and y-intercepts for
f(x)=x^2-7x+10
I was able to get the x-intercepts as (5, 0), (2, 0)
However, I do not know how to get the y-intercepts. I plugged 0 in for x but wouldn;t that make y=(0, 0) and don't you need two for y like you have two for x?

2.) I need to know how for sure to Determine which type of function is used as a model for data, for the scatterplot graph. I have graphs to look at, yet when the line is straight I put lienear and it was wrong, and yet one with curvy lines was a linear. How do I determine correctly every time .

Thanks in advance for the help in case I do not receive an email.
Click here to see answer by stanbon(75887)

Question 130332: My study question asks....Solve the following systems of equation by any method.
All I am asking for is the name of a method so I can look up the order or way to solve it.
3x-2y=12
and
2x+y=8
Thanks!
Click here to see answer by ilana(307)

Question 130354: Ok, so my homework assignment is to write an equation for a parabola. Its coordinates begin at (-3,3), (-2,1), (-1,-1), (0,-3), (1, -1), (2,1), (3,3).
That is the information given- and i am not sure how to continue on to find the equation. I would appreciate your help.
Click here to see answer by solver91311(24713)

Question 130359: Find two positive numbers that differ by 2 and have a product of 20.
Click here to see answer by solver91311(24713)

Question 130393: Find all intercepts for the graph of the quadratic function. f(x)=5x^2-38x+21
Click here to see answer by jim_thompson5910(35256)

Question 130282: Theresa invests $2000 into a GIC which will increase in value at a rate of 4% compounded annually, wheras Steve invests $1000 into a GIC which increases in value at a rate of 6% compounded annually. How many years will pass before Theresa and Steve have the same amount of money ?
Click here to see answer by scott8148(6628)

Question 130455: Can someone assist me. Thank You
f(x)=x^2-2x-6
Click here to see answer by checkley71(8403)

Question 130454: Can someone assist me? Thank You
Find and label the vertex
f(x)=(x+3)^2
Click here to see answer by checkley71(8403)

Question 130471: What is the inverse of y=logbase7 X? I think it is x=7^y ?????
Click here to see answer by ilana(307)

Question 130490: Which function describes the data shown below in the table?
x: -6, 0, 6, 12
y: 81, 27, 9, 3
Is it (a) y=81(3)^x/6 (b) y=81(1/3)^x/6 (c) y= 27(1/3)^6x (d) y= 27(1/3)^x/6? I think it is (b) ????????
Click here to see answer by ilana(307)

Question 130495: sqrt80/81
Click here to see answer by jim_thompson5910(35256)

Question 130496: sqrt35/144
Click here to see answer by jim_thompson5910(35256)

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, 3871..3915, 3916..3960, 3961..4005, 4006..4050, 4051..4095, 4096..4140, 4141..4185, 4186..4230, 4231..4275, 4276..4320, 4321..4365, 4366..4410, 4411..4455, 4456..4500, 4501..4545, 4546..4590, 4591..4635, 4636..4680, 4681..4725, 4726..4770, 4771..4815, 4816..4860, 4861..4905, 4906..4950, 4951..4995, 4996..5040, 5041..5085, 5086..5130, 5131..5175, 5176..5220, 5221..5265, 5266..5310, 5311..5355, 5356..5400, 5401..5445, 5446..5490, 5491..5535, 5536..5580, 5581..5625, 5626..5670, 5671..5715, 5716..5760, 5761..5805, 5806..5850, 5851..5895, 5896..5940, 5941..5985, 5986..6030, 6031..6075, 6076..6120, 6121..6165, 6166..6210, 6211..6255, 6256..6300, 6301..6345, 6346..6390, 6391..6435, 6436..6480, 6481..6525, 6526..6570, 6571..6615, 6616..6660, 6661..6705, 6706..6750, 6751..6795, 6796..6840, 6841..6885, 6886..6930, 6931..6975, 6976..7020, 7021..7065, 7066..7110, 7111..7155, 7156..7200, 7201..7245, 7246..7290, 7291..7335, 7336..7380, 7381..7425, 7426..7470, 7471..7515, 7516..7560, 7561..7605, 7606..7650, 7651..7695, 7696..7740, 7741..7785, 7786..7830, 7831..7875, 7876..7920, 7921..7965, 7966..8010, 8011..8055, 8056..8100, 8101..8145, 8146..8190, 8191..8235, 8236..8280, 8281..8325, 8326..8370, 8371..8415, 8416..8460, 8461..8505, 8506..8550, 8551..8595, 8596..8640, 8641..8685, 8686..8730, 8731..8775, 8776..8820, 8821..8865, 8866..8910, 8911..8955, 8956..9000, 9001..9045, 9046..9090, 9091..9135, 9136..9180, 9181..9225, 9226..9270, 9271..9315, 9316..9360, 9361..9405, 9406..9450, 9451..9495, 9496..9540, 9541..9585, 9586..9630, 9631..9675, 9676..9720, 9721..9765, 9766..9810, 9811..9855, 9856..9900, 9901..9945, 9946..9990, 9991..10035, 10036..10080, 10081..10125, 10126..10170, 10171..10215, 10216..10260, 10261..10305, 10306..10350, 10351..10395, 10396..10440, 10441..10485, 10486..10530, 10531..10575, 10576..10620, 10621..10665, 10666..10710, 10711..10755, 10756..10800, 10801..10845, 10846..10890, 10891..10935, 10936..10980, 10981..11025, 11026..11070, 11071..11115, 11116..11160, 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, 14356..14400, 14401..14445, 14446..14490, 14491..14535, 14536..14580, 14581..14625, 14626..14670, 14671..14715, 14716..14760, 14761..14805, 14806..14850, 14851..14895, 14896..14940, 14941..14985, 14986..15030, 15031..15075, 15076..15120, 15121..15165, 15166..15210, 15211..15255, 15256..15300, 15301..15345, 15346..15390, 15391..15435, 15436..15480, 15481..15525, 15526..15570, 15571..15615, 15616..15660, 15661..15705, 15706..15750, 15751..15795, 15796..15840, 15841..15885, 15886..15930, 15931..15975, 15976..16020, 16021..16065, 16066..16110, 16111..16155, 16156..16200, 16201..16245, 16246..16290, 16291..16335, 16336..16380, 16381..16425, 16426..16470, 16471..16515, 16516..16560, 16561..16605, 16606..16650, 16651..16695, 16696..16740, 16741..16785, 16786..16830, 16831..16875, 16876..16920, 16921..16965, 16966..17010, 17011..17055, 17056..17100, 17101..17145, 17146..17190, 17191..17235, 17236..17280, 17281..17325, 17326..17370, 17371..17415, 17416..17460, 17461..17505, 17506..17550, 17551..17595, 17596..17640, 17641..17685, 17686..17730, 17731..17775, 17776..17820, 17821..17865, 17866..17910, 17911..17955, 17956..18000, 18001..18045, 18046..18090, 18091..18135, 18136..18180, 18181..18225, 18226..18270, 18271..18315, 18316..18360, 18361..18405, 18406..18450, 18451..18495, 18496..18540, 18541..18585, 18586..18630, 18631..18675, 18676..18720, 18721..18765, 18766..18810, 18811..18855, 18856..18900, 18901..18945, 18946..18990, 18991..19035, 19036..19080, 19081..19125, 19126..19170, 19171..19215, 19216..19260, 19261..19305, 19306..19350, 19351..19395, 19396..19440, 19441..19485, 19486..19530, 19531..19575, 19576..19620, 19621..19665, 19666..19710, 19711..19755, 19756..19800, 19801..19845, 19846..19890, 19891..19935, 19936..19980, 19981..20025, 20026..20070, 20071..20115, 20116..20160, 20161..20205, 20206..20250, 20251..20295, 20296..20340, 20341..20385, 20386..20430, 20431..20475, 20476..20520, 20521..20565, 20566..20610, 20611..20655, 20656..20700, 20701..20745, 20746..20790, 20791..20835, 20836..20880, 20881..20925, 20926..20970, 20971..21015, 21016..21060, 21061..21105, 21106..21150, 21151..21195, 21196..21240, 21241..21285, 21286..21330, 21331..21375, 21376..21420, 21421..21465, 21466..21510, 21511..21555, 21556..21600, 21601..21645, 21646..21690, 21691..21735, 21736..21780, 21781..21825, 21826..21870, 21871..21915, 21916..21960, 21961..22005, 22006..22050, 22051..22095, 22096..22140, 22141..22185, 22186..22230, 22231..22275, 22276..22320, 22321..22365, 22366..22410, 22411..22455, 22456..22500, 22501..22545, 22546..22590, 22591..22635, 22636..22680, 22681..22725, 22726..22770, 22771..22815, 22816..22860, 22861..22905, 22906..22950, 22951..22995, 22996..23040, 23041..23085, 23086..23130, 23131..23175, 23176..23220, 23221..23265, 23266..23310, 23311..23355, 23356..23400, 23401..23445, 23446..23490, 23491..23535, 23536..23580, 23581..23625, 23626..23670, 23671..23715, 23716..23760, 23761..23805, 23806..23850, 23851..23895, 23896..23940, 23941..23985, 23986..24030, 24031..24075, 24076..24120, 24121..24165, 24166..24210, 24211..24255, 24256..24300, 24301..24345, 24346..24390, 24391..24435, 24436..24480, 24481..24525, 24526..24570, 24571..24615, 24616..24660, 24661..24705, 24706..24750, 24751..24795, 24796..24840, 24841..24885, 24886..24930, 24931..24975, 24976..25020, 25021..25065, 25066..25110, 25111..25155, 25156..25200, 25201..25245, 25246..25290, 25291..25335, 25336..25380, 25381..25425, 25426..25470, 25471..25515, 25516..25560, 25561..25605, 25606..25650, 25651..25695, 25696..25740, 25741..25785, 25786..25830, 25831..25875, 25876..25920, 25921..25965, 25966..26010, 26011..26055, 26056..26100, 26101..26145, 26146..26190, 26191..26235, 26236..26280, 26281..26325, 26326..26370, 26371..26415, 26416..26460, 26461..26505, 26506..26550, 26551..26595, 26596..26640, 26641..26685, 26686..26730, 26731..26775, 26776..26820, 26821..26865, 26866..26910, 26911..26955, 26956..27000, 27001..27045, 27046..27090, 27091..27135, 27136..27180, 27181..27225, 27226..27270, 27271..27315, 27316..27360, 27361..27405, 27406..27450, 27451..27495, 27496..27540, 27541..27585, 27586..27630, 27631..27675, 27676..27720, 27721..27765, 27766..27810, 27811..27855, 27856..27900, 27901..27945, 27946..27990, 27991..28035, 28036..28080, 28081..28125, 28126..28170, 28171..28215, 28216..28260, 28261..28305, 28306..28350, 28351..28395, 28396..28440, 28441..28485, 28486..28530, 28531..28575, 28576..28620, 28621..28665, 28666..28710, 28711..28755, 28756..28800, 28801..28845, 28846..28890, 28891..28935, 28936..28980, 28981..29025, 29026..29070, 29071..29115, 29116..29160, 29161..29205, 29206..29250, 29251..29295, 29296..29340, 29341..29385, 29386..29430, 29431..29475, 29476..29520, 29521..29565, 29566..29610, 29611..29655, 29656..29700, 29701..29745, 29746..29790, 29791..29835, 29836..29880, 29881..29925, 29926..29970, 29971..30015, 30016..30060, 30061..30105, 30106..30150, 30151..30195, 30196..30240