Questions on Algebra: Quadratic Equation answered by real tutors!

Tutors Answer Your Questions about Quadratic Equations (FREE)

Question 104482: Good morning tutors,
I have a couple of questions. I have to solve and graph these equations and I was wondering if you could help me with these problems?
y = x^2 - 4x
and
y = 2x^2
Thank you very much.
Click here to see answer by ankor@dixie-net.com(22740)

Question 104698: x^2+8X+16=1
Click here to see answer by jim_thompson5910(35256)

Question 104815: please help me solve for x the equation 22=(9+x)x
Click here to see answer by duggie(26)

Question 104861: I'm trying to figure out the roots and the vertex to:2x^+4x-2
Click here to see answer by HyperBrain(694)

Question 104934: a toy rocket is launched from the top of a building 50 ft. tall at an initial velocity of 90 ft per second. Let t represent the amount of time elapsed after the launch. Solve.

the answer is y= -16x2 + 90x + 50
How did the get the -16x squared??
Click here to see answer by Earlsdon(6294)

Question 104971: Simplify. 3/4 divided by 4/5

Click here to see answer by Fombitz(32388)

Question 104968: Solve. x^2 + 6x � 27 = 0
Click here to see answer by jim_thompson5910(35256)

Question 105072: Tutor,
I am think this is incorrect could you please help me with this problem:
Solve by using the quadratic formula
4x^2 - 3x + = 0 (no real number solutions?)
and
X^2 + x - 2 = 0 (is this 1,2 ?)
Any help is appreciated.
Click here to see answer by jim_thompson5910(35256)

Question 105083: Tutor,
I am having problems getting the correct sign. I would appreciate your help with these two problems.
Solve:
x^2 + 8x - 20 = 0 (10 and 2 are the numbers which are negative and possitive)
and
x^2 + 16x + 60 = 0 (6 and 10 are the numbers I have the same problem)
I have the most difficulty with the signs I am not sure I am getting the right negatives and possitives. Thank you for your guidance on my problems.
Click here to see answer by Earlsdon(6294)

Question 105112: Good Morning Tutor,
Could you tell me if I have these problems correct?
Solve:
x^2 + 7x - 1 = 0 is (-6 +- sqrt of 50 / 2)
Solve by completeing the square:
2x^2 + 8x - 5 = 0 is (4 +- sqrt of 26 / 2)
Thank you for your help this morning.
Click here to see answer by MathLover1(20849)

Question 105122: Need help solving: 3x^2-2x+1=0 using the quadratic formula. I'm getting weird answer and it is confusing me.
Click here to see answer by MathLover1(20849)

Question 105139: Please help me solve.
Multiply. n^2-n-20/2n^2 x n^2+5n/n^2-25
Click here to see answer by Fombitz(32388)

Question 105141: Please help me solve.
sq rt (3x+6) -3=0
Click here to see answer by Fombitz(32388)

Question 105128: Z + 1/Z = 1
Z ^64 + 1/ Z^64 = ?
Click here to see answer by Fombitz(32388)

Question 105194: Hello Tutor,
I am in need of some help if you can help me out I would appreciate it.
Solve by completing the square:
1.) 4x^2 + x - 3 = 0 I got -3/4 , 1 is this correct?
2.) x^2 = 5x + 2 I think this is 5 +- sqrt of 33 / 2 is this correct?
3.) 4x^2 + 2x - 3 = 0 I got -1+- sqrt of 13 / 8 is this correct?
I am not sure I am solving these questions of completing the squares correctly if you could tell me if I have them correct I would appreciate it. Thanks in advance.
Click here to see answer by edjones(8007)

Question 105207: Could you help me with this problem?
The demand and supply equations for a certain item are given by
D= -15p + 30
S= -p^2 + 20p - 18
Find the equilibrim price.
I have gotten serveral different answers however is the answer $1.43?
Click here to see answer by edjones(8007)

Question 105138: the demand and supply equations for a certain item are given by
D= -5p+40
s= -p+30p-8
Find the equilibrium price.
Click here to see answer by elima(1433)

Question 105195: Tutor if you could help me with this I would appreciate it. I need to find the table of values for y= -x^2 - 2x and for y = x^2 - 1. Thank you for your help.
Click here to see answer by checkley75(3666)

Question 105218: 1/x-4 +x/x-5 +1/x^2-9x+20=0 I have to solve for x I have the LCD to be(x-4)(x-5) I multiplied the numerator times the LCD and got (x-5)+x(x-4)+1=0. Next I got x-5+x^2-4x+1=0. I combined my like terms and got -3x-4+x^=0. The x ^2 keeps throwing me off because I don't know what to do with it. Please show me what to do.
Click here to see answer by jim_thompson5910(35256)

Question 105088: Good Evening tutor,
Could you tell me if I have these correct?
Solve by completing the square:
1.) 4x^2 + 2x - 3 = 0 is (-1+-sqrt of 13 / 8)
2.) x^2 = 5x + 2 is (5 +- sqrt of 29 / 2)
3.) 4x^2 + x - 3 = 0 is (1, -3/4)
I want to make sure I solved these correctly so any assistance is very much appreciated. Thank you in advance.

Click here to see answer by checkley75(3666)

Question 105255: how do i write this function in standard quadratic equation form?
1.) y = -(3x-4)^2 + 6
Click here to see answer by Earlsdon(6294)

Question 105257: what can a and k be so both points are on the graph of function?
points are (1,11) and (2,-19); function is y= a(x+1)^2 + k
how can i find the function so that both poitns are on the graph??
Click here to see answer by Earlsdon(6294)

Question 105256: what can a and k be so both points are on the graph of function?
points are (0,1) and (2,1); function is y= a(x-1)^2 + k.
how can i find the function so that both poitns are on the graph??
Click here to see answer by edjones(8007)

Question 105254: find quadratic function ax^2 + c with a graph that has the given points:
1.) (2, 5/2) and (0,-1/2)
using those points, how can i come up with the function??
Click here to see answer by edjones(8007)

Question 105344: 3x^2 - 4x - 7 = 0
and
x2 + 5x - 6 = 0
Very confused.
Click here to see answer by checkley75(3666)

Question 105344: 3x^2 - 4x - 7 = 0
and
x2 + 5x - 6 = 0
Very confused.
Click here to see answer by scott8148(6628)

Question 105453: The product of two numbers is 5 and the sum of their reciprocals is 9/10. Find the numbers.
Click here to see answer by checkley75(3666)

Question 104635: solve the following equation for x
2x^2-4t+4=6
Click here to see answer by rahul(6)

Question 105586: Problem. Identify the axis of symmetry, create a suitable table of values and sketch the graph. The problem is y=x^2-5x+3. I've identified the axis of symmetry as 5/2 but I am having difficulty creating the table of values. Any assistance would be greatly appreciated.
Click here to see answer by MathLover1(20849)

Question 105695: 3x^2+17x+45=12
Click here to see answer by Fombitz(32388)

Question 105812: Please Help. I have a textbook and it takes me through the steps on what I need to do, but I still do not understand exactly why I need to do all these steps. My problem does not come from a textbook that I know of. I only havce the text for guidance. This is my problem: solve quadratic equation by using quadratic formula. x^2-x-6=0 This is what I have done so far, but I know it is not correct. x^2-x-6+6=0+6 x^2-x=6 x=6 If you could help I would greatly appreciate it. And I thank you for your time.
Click here to see answer by Fombitz(32388)

Question 105663: I NEED SOME HELP WITH SOME PROBLEMS ON QUADRATIC EQUATIONS....
1) (2+X)SQUARED=49
2) (X+2)(3X-4)=(X+5)(2X-5)
3)CAN NOT TELL IF THE EQUATION IS RATIONAL OR IRRATIONAL...8XSQUARED=14X-3
4)S=SO+GTSQUARED+K FOR T WITH THE DENOMINATOR OF 0

Click here to see answer by MathLover1(20849)

Question 105885: Ok, I don't know where to go to solve a formula help, so is anyone able to help solve the following formula for me? I am going crazy here.
Solve the Formula D=1/8 s i for the variable s? Thank you very much!
Click here to see answer by edjones(8007)

Question 105856: word problems-quadratic equation
Students sent flowers costing $20 to a sick classmate. There were four fewer students contributing than was planned, requiring each of the others to give 25 cents more. How many students contributed to the gift?
Click here to see answer by scott8148(6628)

Question 105857: word problem-quadratic equation
Three pieces of rod measure 20 cm, 41 cm and 44 cm. If the same amount is cut off each piece, the remaining lengths can be formed into a right triangle. What length is cut off?
Click here to see answer by scott8148(6628)

Question 105940: how do you solve 11x(16x-12)=0 using the null factor law

Click here to see answer by scott8148(6628)

Question 105927: word problems-quadratic equation
A storeowner buys a quantity of balls for $600. If they had each cost $0.25 less, she would have had 10 more for the same money. How much did she pay for each ball??
pls help me! anyone?? just set up the formula for me.. tnx. =D
Click here to see answer by scott8148(6628)

Question 105946: Can some one be so kind as to help me using the Quadriatic formula and solve the following equation? 17x+ 6 = 28x^2
Thank You for helping me.
Click here to see answer by edjones(8007)

Question 105974: how do you change 2x(x+2)+3=1 into the form of ax^2+bx+c=o
Click here to see answer by edjones(8007)

Question 105953: I did not find any solvers to help me with trying to solve this problem , can someone here please help?
Question? Use a special product formula to factor the perfect square trinomial, 49x^2 - 42x + 9.
Thanks.
Click here to see answer by alvinjohnburgos(11)

Question 105854: quadratic equations-word problem
Chris cuts half a rectangular lawn, 40m by 30m, by mowing strips around the perimeter. Jerri cuts the small rectangle left. How wide a strip does Chris cut so that they share the work equally?
Click here to see answer by ankor@dixie-net.com(22740)

Question 106016: Find the slope of the line passing through the pair of points or state that the slope is undefined.
(7,4) and (7,6)
Find the slope of the line
y=-5/7x - 9
Find the y-intercept
y=8x-1

Click here to see answer by HyperBrain(694)

Question 106068: Please help with the the equation
I understand a= 1 b=-4 c=1
and using
Why is the the discriminant:
and not
Shouldnt equal -4 not 4
Thanks

Click here to see answer by jim_thompson5910(35256)

Question 106110: The sign of the discriminant D is positive as the parabola opens upward.
We observe the x intercepts to be �1, and 0.67
So the function is written as y = a(x � (-1)) (x � 0.67) where �a� is a constant.
y = a (x + 1) (x � 0.67)
The lowest point of the parabola is the vertex.
Now the parabola passes through (- 0.16, -2)
-2 = a( - 0.16 + 1) ( - 0.16 � 0.67)
-2 = a(0.84) (- 0.83)
a = -2/ (0.84)(- 0.83)
a = 2.87
Thus the quadratic equation is y = 2.87 ( x + 1) (x � 0.67)
Or y = 2.87 (x2 + 0.33x � 0.67)
The quadratic equation is 2.87 ( x2 + 0.33x � 0.67 ) = y
To solve for x, we equate y to 0.
x2 + 0.33x � 0.67 = 0
x2 + 0.33x � 0.67 = 0
x2 + x � 0.67 x � 0.67 = 0
x (x + 1) � 0.67 ( x + 1) = 0
(x + 1) (x � 0.67) = 0
X + 1 = 0 or x � 0.67 = 0
X = -1 or x = 0.67
The solution is x = -1 or x = 0.67
This is a discussion group question. One of the girls on my team came up with this but I can't figure out where she got the 0.33x. I thought I was getting it but now I am confused. Can you explain this? Please, Please!
Click here to see answer by Fombitz(32388)

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