Questions on Algebra: Quadratic Equation answered by real tutors!

Tutors Answer Your Questions about Quadratic Equations (FREE)

Question 139623: What are the pros and cons of solving quadratic equations using graphing, using the quadratic formula, completing the square, and factoring.
Click here to see answer by ankor@dixie-net.com(22740)

Question 139689: Ethel tosses a softball upward. When the ball leaves her hand 5 feet above the ground it has an initial upaward velocity of 66 feet per second. How high can Ethel toss the ball?

HeLP!
Click here to see answer by ankor@dixie-net.com(22740)

Question 139775: x2+4x-21=0
trying to find the two solutions??? I was fine till c was a value... when c = o I had no problems solving now that c = a value.. im stuck help i can get this far:
a=1
b=4
c= -21 -4+_ 4sqd + 4(1)(-21) divided by 2(1)

then, -4+- 4sqd + -84 divided by 2
then i get confused.... help

Click here to see answer by jim_thompson5910(35256)

Question 139631: The revenue R (in millions of dollars) of a large retail store can be modeled by R=1.23t^2-2.22t+8.5, where t is the number of years since 1990. Estimate the year in which the store's revenue will reach 90 million dollars?
HELP!!
Click here to see answer by ankor@dixie-net.com(22740)

Question 139853: Please help me solve this equation:
5x+4y=12
I have tried the equation by doing this:
5x+4y=12
5x-5x+4y=12-5x
4y=12-5x
4y/4=12-5x/4
My answer came totaled to: y=3-5x
Click here to see answer by jim_thompson5910(35256)

Question 139858: A ramp-to-ground motorcycle jump can be modeled by the quadratic function
h = -0.0022d2 + 0.46d + 19,
where d is the distance in feet along the ground from where the motorcycle left the ramp and h is the height of the motorcycle in feet. How long was the jump?
Round your answer to two decimal places. The units will be typed in the second box.

Click here to see answer by stanbon(75887)

Question 139966: A parabola passes through (-2,0),(4,0) and (5,14).
Find the equation of the axis of symmetry.
Find the equation of the line perpendicular to the Y-axis that passes through exactly one point of the parabola.
find the equation of the parabola.
I just do not know where to start, what to look for first. Please help. Thankyou.
Click here to see answer by scott8148(6628)

Question 140056: A ball is thrown vertically upwards from the balcony of an apartment building. The ball falls to the ground. The height of the ball , h metres, above the ground after t seconds is given by h=-5t^2 +15t +45.
What is the height of the balcony? 45m?
What is the maximum height reached by the ball?
When will the ballreach a height of 55m?
When will the ball hit the ground?
Click here to see answer by rapaljer(4671)

Question 140075: three man can finish a painting job in 8 days. This job can be finished by 5 women in 6 days and by 8 boys in 10 days. how long will it take 1 man 2 women and 3 boys working together?
Thanks! I will make a donation to you for your help.
Click here to see answer by ankor@dixie-net.com(22740)

Question 140112: If 6 is added to a number and then subtracted from the same nunber, the product of the sum and the difference 189. What is the number? Totally stumped
Click here to see answer by jojo14344(1513)

Question 140240: (x-2)^2=0
Click here to see answer by checkley77(12844)

Question 140241: x^2+4x+1=0
Click here to see answer by checkley77(12844)

Question 140237: 64x^2-81=0
Click here to see answer by checkley77(12844)

Question 140238: x^2+4x+1=0
Click here to see answer by jim_thompson5910(35256)

Question 140201: Find an equivelent expression without parentheses.
-(23r + 8s -23)=
Please help me with this one too.
Click here to see answer by stanbon(75887)

Question 140301: Thanks in advance for helping me. Write the quadratic equation for the set of roots 4, -6
Click here to see answer by ankor@dixie-net.com(22740)

Question 140326: The difference between two positive numbers is 4. If twice the square of the larger number is added to three times the smaller the sum is 53. Solve.
This is what I have
x - y = 4
2x squared + 3y = 53
This is where I got lost.
Thank you
Click here to see answer by ankor@dixie-net.com(22740)

Question 140344: Please show me how to find and graph the derivative value? Thanks!
given: y = X^2
at X = 3
and
at X = -1
Click here to see answer by Fombitz(32388)

Question 140384: Solve 2x*squared* - 5x=5 by completing the square.
Click here to see answer by ankor@dixie-net.com(22740)

Question 140384: Solve 2x*squared* - 5x=5 by completing the square.
Click here to see answer by stanbon(75887)

Question 140475: for the derivative value I need to show tongant line in graph? Thanks
Given y=X^2
at x = -2
So far I have
At X=-2, the derivative is 2(-2)= 0 (please show graph).
Click here to see answer by stanbon(75887)

Question 140507: The area of a rectangle is the product of its length and width, and equals 1062. If the length is 5 more than three times the width, find the width of the rectangles.
Please help me thank you.
Click here to see answer by scott8148(6628)

Question 140500: can someone please show ma how to do this .thanks in advance for your help.find the roots of each quadratic equation by factoring.
1. x^2-6xi got 2,4
2.x^2-9/4x-25 i got 4x3-100x-9/4x
Click here to see answer by stanbon(75887)

Question 140561: Solve by the elimination method.
3x + 4y = 3
6x + 8y = 6
Can someone please help me with this. I was doing really well with my work but now am stuck again. Help me please.
Click here to see answer by checkley77(12844)

Question 140566: how do you do a quadratic equation without a b value?
Click here to see answer by oscargut(2103)

Question 140566: how do you do a quadratic equation without a b value?
Click here to see answer by ptaylor(2198)

Question 140548: please help.find the roots of the quadratic equation y=x^2+7x-18 by factoring Thanks
Click here to see answer by oscargut(2103)

Question 140599: Solve and graph.
3x + 9 >_ -15 or 3x + 1 >_ -8
The solution is ??
Help me with this of course the <_ is supposed to be over each other.
The graph's are number lines and are supposed to have either a ( or a [ on the one end and i have no idea how to do these the right way can someone hlp.
Click here to see answer by stanbon(75887)

Question 140597: The perimeter of the rectangle is 190 inches. The length exceeeds the width by 53 inches. Find the length and the width.
Can someone please help with this one please? The perimeter is the 190 diveded by 4? Is that the way to start or not?
Click here to see answer by jojo14344(1513)

Question 140609: Write the expression in quadratic form, if possible;
a8 + 10a2 - 16
Click here to see answer by MeggieMizell(6)

Question 140596: Can someone help me with this one?
Solve this using the substitution method.
3m n = 18
m - 4n = 32
Yikes I really have not figured out how to do these correctly will someone help.
Click here to see answer by MeggieMizell(6)

Question 140594: Miguels insurance will replace his car if costs exceed 80% of the cars value. The car substained $11200 worth of damage, but it was not replaced. What was the value of the car.
What was the value of the car?
Help. Do I multiply 80% by $11200 to get the value of the car?
Click here to see answer by jojo14344(1513)

Question 140640: solve equation using imaginary and complex numbers x^2+4x+24=0
please help! =)
Click here to see answer by jim_thompson5910(35256)

Question 140602: could someone please show me how to do this problem.thanks .
write the equation of the root 2,3
Click here to see answer by edjones(8007)

Question 140595: Is the ordered pair a solution of the inequality?
(-5, 6); 6x + y < -8
Help please
Click here to see answer by edjones(8007)

Question 140676: I need to solve 5x+4y=12 for y. I have tried 5-5x+4y=12-5 4y/4=7/4
From there I'm stuck and I not sure if that is even right because I don't know how to check my work for this type of equation. Thanks, Julie.
Click here to see answer by checkley77(12844)

Question 140743: please help!! use the quadratic equation -b+ (tiny line under the plus sign) sqrt(b^2-4ac)/2a to find the roots of the equation x^2-3x+2=0 thanks for your help.I really appreciate all ya'll do.
Click here to see answer by c-dubb swimmer(3)

Question 140763: Hi I am bnot sure how to do these two problems. I hope some one can help me. Thank you very much.
1. Solve by factoring:
x2 � 9x = -8
2. Solve using the square root property:
2x2 � 5 = 93

Click here to see answer by checkley77(12844)

Question 140774: cpuld someone check this for me.Thanks in advance for your help.
solve the equation by completing the square
x^2+8x-13=0 i got x=-4+sqrt 29,-4- sqrt 29
Click here to see answer by stanbon(75887)

Question 140834: I need help obtaining the derivative value for given:
y=X^2-4X+5

Click here to see answer by stanbon(75887)

Question 140705: Please help me to obtain the derivative. for given: Y=x^2-4X+5
I think the original points are: (X1, X2-4x+5)
and second point should be (x + h, (X + h)^2
next I need to find oy and ox (which = the y2 + y1 and x1 + x2)
This is where I get confused, I don't know what to do next.
Click here to see answer by stanbon(75887)

Question 140832: Please help!! write the equation of the root
-3/4, 8 thanks for the help.
Click here to see answer by Earlsdon(6294)

Question 140846: please help. write the equation of the root
6,-2/3 thanks for your help
Click here to see answer by jim_thompson5910(35256)

Question 140648: The path of a falling object is given by the function s= -16t^2 +v0t +s0 where v0 represnts the initial velocity in ft/sec and s represents the initial height. The variable t is time in seconds, and s is the height of the object in feet. So if a rock is thrown upward with an initial velocity of 32 ft per second fron the top of a 40-ft building. How high is the rocke after 1 second?after 0.5 seconds? How many sec will it take the rock to reach maximum height before it's downward fall?
Click here to see answer by ankor@dixie-net.com(22740)

Question 140865: helpp!! use the quadratic formula x=-b+(small line under the plus sign) sqrt(b^2-4ac)/2a to find the root of the equation
x^2-4x-6=0 thank you for your help
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, 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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, 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