Questions on Algebra: Quadratic Equation answered by real tutors!

Tutors Answer Your Questions about Quadratic Equations (FREE)

Question 678270: Write a quadratic function that fits each set of points.
(1,2), (2,-1), and (5,2)
Click here to see answer by lynnlo(4176)

Question 678366: Solve and check
29x^2-18x=0
Click here to see answer by ReadingBoosters(3246)

Question 678366: Solve and check
29x^2-18x=0
Click here to see answer by lynnlo(4176)

Question 678431: How can I solve for x using the quadratic formula.
2x=(x+1)/(x-1)
Thank you very much
Click here to see answer by ReadingBoosters(3246)

Question 678441: Write a quadratic equation which has solutions of +- 7i
Click here to see answer by jsmallt9(3758)

Question 678412: There are 10 tonnes of potatoes in a large container. Bags of potatoes of nominal mass 5kg are filled from this container.
the potatoes are not all the same size and it is not possible to make the bags exactly 5kg. (1 tonne = 1000kg)
1) If all the bags could be made with a mass of exactly 5kg. How many bags would be filled from the container?
My answer: 10000 / 5 = 2000
The bags could be light by up to xkg or too heavy by up to xkg
2) State , in terms of x, the largest and smallest number of bags that can be filled from the container
My answer: Largest number 10000 / (5 - x), Smallest number 10000 / (5 + x)
3) Given that the largest number of bags is 100 times more than the smallest number of bags, write down an equation in x and show that it simplifies to x2 ( x squared) + 200x - 25 = 0
My answer: ??? Can't remember how to do these
4) Solve this equation and hence work out the largest and smallest mass of a bag of potatoes.
My answer: and therefore this
Click here to see answer by jsmallt9(3758)

Question 678720: factorise 2x2-x-3=0
Click here to see answer by MathLover1(20849)

Question 679004: factor x^2-13x-8330
Click here to see answer by DrBeeee(684)

Question 678888: In this problem, I am supposed to:
(a) using a graphing calculator to graph the equation
(b) use the graph to approximate any x-intercepts of the graph
(c) set y=0 and solve the resulting equation
(d) compare the result of part (c) with the x-intercepts of the graph.
For part (a) I got the x-intercepts -1 and -5.
When I did part (c) I got -1, but I have no idea how to get the -5...
How do you solve for x twice??
Click here to see answer by pmatei(79)

Question 679156: 2x�+x+4
Click here to see answer by ReadingBoosters(3246)

Question 679490: whats the equation for f(x)=x^2 is vertically stretched by a factor of 9 and translated 2 units to create g
Click here to see answer by stanbon(75887)

Question 679628: 2*x^2-10*x-48 =0
Click here to see answer by checkley79(3341)

Question 679745: solve by completing the square: 4x^2+4x-15=0
Click here to see answer by lynnlo(4176)

Question 679859: for each equation, determine what type of number the solutions are and how many solutions exists.
x^2+10x+11=0
i've tried to do it with the quadratic equation but im not sure if i have to use the quadratic equation.
Click here to see answer by ReadingBoosters(3246)

Question 679857: for each equation, determine what type of number the solutions are and how many solutions exists.
x^2+10+11=0
i've tried to do it with the quadratic equation but im not sure if i have to use the quadratic equation.
Click here to see answer by ReadingBoosters(3246)

Question 680032: How do i find the complex zeros of quadratic Functions, such as this one.
g(x)+4x^2-3x+1
Click here to see answer by ReadingBoosters(3246)

Question 680000: X^2=-5X-3
Click here to see answer by ReadingBoosters(3246)

Question 680163: Please help me solve this word problem using the position equation. I have solved the first part but cannot seem to get the second part!
A C-141 Starlifter flying at 25,000 feet over level terrain drops a 500-pound supply package.
(a) How long will it take until the supply package strikes the ground?
This is what I have come up with:
s=-16t^2+v0t+s0
Since we don't know the velocity, plug in 0 for v0t.
s=-16t^2+0+25,000
0=-16t^2+25,000
16t^2=25,000
t^2=25,000/16
square root of t^2=square root of 25,000/16
t approximately = 39.5 seconds
Now, here's the part I can't seem to figure out.
(b) The plane is flying at 500 miles per hour. How far will the supply package travel horizontally during it's descent?
Click here to see answer by Alan3354(69443)

Question 680269: (x+1)^2=x+1
Click here to see answer by ReadingBoosters(3246)

Question 680405: A toy rocket is launched from ground level. Its distance in feet from the ground in t seconds is given by the formula s(t)=-16t^2+208t
(a) make a sketch of what is happening
(b) When will the rocket be 550 feet from the ground
(c) After how many seconds will the rocket strike the ground?
Click here to see answer by MathLover1(20849)

Question 680502: solve for x
9x^2-28=0
Click here to see answer by jim_thompson5910(35256)

Question 680789: use the quadrtic formula for:

4x^2+x-3=0
Click here to see answer by mananth(16946)

Question 680795: use the quadratic formula for :
4x^2+4=17x
my answer:
4x^2+4=17x
4x^2+4-17=0
(-17)^2-4(4)(4)=225
___
17(+/-) /225
___________ = 17(+/-)15 /8
8
root: 4, (1/4)
is this right?

Click here to see answer by mananth(16946)

Question 680885: I'm supposed to solve the equation, (4/5)(x^2)=x, using the qudratic formula.
Click here to see answer by ReadingBoosters(3246)

Question 680880: (find solution set) solve the following equation using the quadratic formula:
x^2-10x-48=0
Click here to see answer by ReadingBoosters(3246)

Question 681243: What is the x-value of the vertex of the quadratic function y= -5x2 +4/7? Explain.
Click here to see answer by solver91311(24713)

Question 681469:
Click here to see answer by MathMan88(14)

Question 681503: 3(5+3x)-(x-3)=0
15+9x-x+3=0
18+8x=0
8x=-18
x=-9/4=2.25
If the above is correct, if I put x back into the original equation:
3(5+(3x2.25))-(2.25-3)=0
3(5+6.75)-(-0.75)=0
3x11.75+0.75=0
35.25+0.75=0
36=0!!
That seems nonsensical. I would be very grateful for an explanation and solution to this problem.

Click here to see answer by MathTherapy(10549)

Question 681607: x^2(x+2)-2x(x+2)-3(x+2=0
Click here to see answer by funmath(2933)

Question 681701: The discriminant of 3x^2 - 2x - 1 = 0 is?
Click here to see answer by Alan3354(69443)

Question 681783: Solve y2-10y+25=0,using completing the square method
Click here to see answer by stanbon(75887)

Question 681794: Help explain why this expression cannot be factored
40a^2+21a-2
Click here to see answer by jim_thompson5910(35256)

Question 681972: What is the factored form of 4x^2-32x+164
Click here to see answer by Alan3354(69443)

Question 682089: seven years ago varun's age was five times the square of swati's age. three years hence swati's age will be two fifth of varun's age.find their present ages
Click here to see answer by lwsshak3(11628)

Question 682133: Hello,
I wanted to see if I was doing this problem correctly.
I started the answer with -16t^2+16t+410=90, then subtracted 90 to get -16t^2+16t+320=0 and then perform the quadratic equation to get the answer. Is this the right start?

The function h(t) = -16^2+16t+410 gives the height h, in feet, of a coin tossed upward from a balcony 410 ft high with an initial velocity of 16 ft/sec. During what interval of time will the coin be at a height of at least 90 ft?
Thanks
Click here to see answer by nerdybill(7384)

Question 682268: Greetings, I am doing homework on a website.
Here is the problem: Write a quadratic function to model the graph (a graph is provided but is not vital for the tutor to understand my question.).
The coordinates of the vertex are (h,k)= (3,2)
when substituted the values into the equation the equation becomes

Why is h=3 in the ordered pair of the vertex but it is 9 in the vertex form equation?

Click here to see answer by MathLover1(20849)

Question 682381: compute the discriminant of the quadratic equation 10 x 2 + x - 3 = 0
Click here to see answer by lynnlo(4176)

Question 682430: Bill can row 3 mph in still water. It takes him 3 hr 36 min to go 3 mi upstream and then return. Find the speed of the current.
Click here to see answer by mananth(16946)

Question 682651: Can you help me solve this -> g(x) = 3 x2 - x + 8 < using the quadratic formula?
Click here to see answer by vleith(2983)

Question 682707: what is the vertex form of y= - 1/3 + 2x + 7/3
Click here to see answer by solver91311(24713)

Question 682710: what is the vertex form to -3y=x^2-6x-7
Click here to see answer by lynnlo(4176)

Question 682722: I answered the equation 9x^2=36 in what i thought was quadratic form but my professor informed me that it was not, i got the answer 2,-2 which was correct.. what are the correct steps to this problem?

Click here to see answer by lynnlo(4176)

Question 683186: what is the vertex form of y=3x^2-24x +21
Click here to see answer by nerdybill(7384)

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