Questions on Algebra: Quadratic Equation answered by real tutors!

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Question 141322: Solve for x:
sqrt x-6 + sqrt x+6 = 6
a. 3
b. 16
c. 10
d. Cannot be solved
This is what I have but it is not an answer.
sqrt x-6 = sqrt x+6 +6
(sqrt x-6)^2 = (sqrt x+6+6)^2
(sqrt x+6)^2 + 2 * sqrt x+6*6+6^2
x+6 + 2 sqrt x+6 + 6 + 36
(sqrt x-6)^2 = (sqrt x+6+6)^2
x-6 = x + 6 + 2sqrt x+6+36
x-6 + x + 42 + 2sqrt x+6
2x - 6 = 2sqrt x+6
4x^2 + 36x - 36 + 4 (x+6)
4x^2 + 36x - 36 = 4x + 24
4x^2 - 32x = 0
4x(x - 8x) = 0
4x = 0 and x - 8 = 0
x = 0 x = 8
Click here to see answer by stanbon(75887)

Question 141308: Which method is best used to find the solutions to:
k(w) = -w^2 + 4
a. Using the square root property
b. Completing the square
c. Using the quadratic formula
d. This cannot be solved since the variable is not 'x'
I selected D; because a,b,c all require a 'x' variable
Click here to see answer by scott8148(6628)

Question 141273: write the equation of the asix of symmetry, and find the coordinates of the vertex of the graph of each function. Identify the vertex as a maximum or minimum. Then graph the function.
Click here to see answer by solver91311(24713)

Question 141346: 2x^2 - 3xy +y^2 =14
2x - y = 7
Please help having hard time solving this one. Thank you
Click here to see answer by nabla(475)

Question 141391: Use the distributiive law to help solve.
6(w-2)= -12
I do not understnad the distributive law what is it.
Click here to see answer by checkley77(12844)

Question 141405: Solve
0.4x + 3 <_ 1.2x -6
the solution is {x l x ? ?}
Can someone help me with this one please??
Click here to see answer by stanbon(75887)

Question 141381: Solve
-0.4x < -24
How do i do this one???
Click here to see answer by checkley77(12844)

Question 141481: please help.write the equation of the line

line y(2,11) line z(-1,-1) hope you understand this.Thanks for the help.
Click here to see answer by stanbon(75887)

Question 141484: please help.
suppose a bag contains 6 marbles.one is white,two are red,and three are yellow.each time a marble is taken out,it is replaced.find P (red and yellow)

thanks in advance for the help.
Click here to see answer by stanbon(75887)

Question 141485: help!! a rectangle has a length 4 cm greater than it's width.it's area is 45 cm^2.what are the length and width of the rectangle. thanks for helping.
Click here to see answer by ankor@dixie-net.com(22740)

Question 141505: What is the maximum value of q(x) = (x-4)^2 - 13?
a. -4
b. 4
c. -13
d. There is no maximum value
Click here to see answer by checkley77(12844)

Question 141572: A framer at a photo gallery wants to frame a print with a matte of uniform width all around the print. To make it pleasing to the eye, the area of the matte should equal the area of the print. If the print measures 40 cm by 60 cm, how wide should the matte be?
Click here to see answer by edjones(8007)

Question 141577: Raj and his sister cut the lawn. The lawn is a square and Raj says he will cut a path around the outside 3m wide. His sister will cut the remaining lawn. If the part he cuts is the same area as the part she cuts, what are the dimensions of the lawn?
Click here to see answer by scott8148(6628)

Question 141590: A 60cm length of rope is to be cut into two pieces to form the perimeters of two squares. If the total area of the two squares is to be a minimum, what are the dimensions of the squares?
Click here to see answer by edjones(8007)

Question 141566: The width of a rectangle is 4 cm less than the length. The area is 350cm^2. Find the length and width.
Click here to see answer by jojo14344(1513)

Question 141673: A model rocket is shot straight up from the roof of a school. The height at any time t is approximated by the model H=15 + 23t - 5t^2,where H is the height in metres and t is the time in seconds.
a)how long does it take for the rocket to pass a window 10 m above the ground.
b) when does the rocket hit the ground?
c) what is the maximum height the rocket reaches above the roof of the school?
Click here to see answer by stanbon(75887)

Question 141698: Sorry the question wasnt done yet...Find the indicated outputs for
f(x)= 2x2 - 5x
(The second 2 is too the power of)(one of those little 2's above the number)
f(0)=
f(-1)=
f(2)=
HELP PLEASE!!!!!
Click here to see answer by stanbon(75887)

Question 141699: Trains A and B are travelling at the same direction on paralell tracks. Train A is travelling at 40 miles per hour and Train B is travelling at 60 miles per hour. Train A passes a station at 3:25 AM. If train B passes the same station at 3:37AM. At what time will train B catch up with train A??
How do I figure this one out??
Click here to see answer by stanbon(75887)

Question 141713: Graph on a number line where x is a real number.

Will someone please help me with this one????
Click here to see answer by stanbon(75887)

Question 141713: Graph on a number line where x is a real number.

Will someone please help me with this one????
Click here to see answer by Edwin McCravy(20054)

Question 141576: A model rocket is shot straight up from the roof of a school. The height at any time t is approximated by the model H = 15 + 23t -5t squared, where H is the height in metres and t is the time in seconds.
a) How long does it take for the rocket to pass a window 10 m above the ground?
b) When does the rocket hit the ground?
c)What is the max height the rocket reaches above the roof of the school?
Click here to see answer by ankor@dixie-net.com(22740)

Question 141711: Solve using the multiplication method.Please also do a check.
-1/6x = -9/10
these are fractions and i do not no what i am doing.Help me please.
Click here to see answer by stanbon(75887)

Question 141701: Solve by the elimination method.
7r - 5s =-18
5r + 7s = 40
Help me please. This is getting sooooo much harder and I am grasping none of it.This is terrible!!!
Click here to see answer by scott8148(6628)

Question 141840: Hi I need help in understanding one of the steps in "completing the square" for a quadratic equation.Here is my problem
x^2+9x+8=0
IN the 2ND step my homework tells me that I have to multiply the equation by A, whatever value it has.Now everytime they show a model there is a different value for "A" everytime.How do I find the value of "A" for my own homework equations.Here is one of my models from my school...

Solve x^2 + 7x + 12 = 0 by completing the square.
1. Write the quadratic equation in general for and identify A and B.
A is 1 and B is 7.
2. Multiply the terms of the equation by 4A.

4A is 4: 4[x^2 + 7x + 12]= 4[0]
4x^2 + 28x + 48 = 0
3.Isolate the constant term on the right side of the equation.
4x^2 + 28x = -48
4.Add B^2 to each side of the equation.
B^2 is 49: [4x^2 + 28x] +49 = [-48]+49
4x^2 + 28x + 49 = 1
5.Factor the left side of the equation to the square of a binomial.
(2x + 7)(2x + 7) = 1
(2x + 7)^2 = 1
Now solve:
1^2 is 1, so (-1)^2 is 1, so
2x + 7 = 1 2x + 7 = -1
2x = -6 2x = -8
x = -3 x = -4

The solution set is {-4, -3}.
What I dont understand is step 2 how did they decide to multiply the equation by 4? Why dont they use any other number like 2 or 6?

I hope I gave you enough information.Thanks for your help...
Click here to see answer by nabla(475)

Question 141709: The length of a rectsngle is fixed at 14cm. What widths will make the perimeter greater than 86cm? the width must be bigger than ___?
Will someone help me with this I cannot do word problems at all!!!
Click here to see answer by ankor@dixie-net.com(22740)

Question 141874: Solve the following system of equations.
x+2y=7 (1)
x=8-2y (2)
How do I do this one???
Click here to see answer by rapaljer(4671)

Question 141873: Translate to an algebraic expression.
The product of 16% and some number.
I do not understand this one at all will someone help please.?
Click here to see answer by rapaljer(4671)

Question 141872: Graph the equation using the slope and y-intercept.
y = 9/4x + 7 (the 9/4 is a fraction)
HELP PLEASE
Click here to see answer by rapaljer(4671)

Question 141870: Solve. Then Graph.
7x >_ 63 (The _ is supposed to be under the >)
Would the solution be {xlx<9} ?? AND
the graph be a hollow circle on the 9 and and arrow towards the numbers higher than 9? Am I even close?

Click here to see answer by rapaljer(4671)

Question 141902: How do you find the term that should be added to the expression to make a perfect square trinomial?
x^2 + 11x
x^2 + 4/5x
how?
Click here to see answer by Earlsdon(6294)

Question 142110: SOLVE.
5/8x + 1/16x = 3/16 + x
(these are all fractions)
HELP, how do I do this? Do i have to change the 5/8 to 10/16x?
Click here to see answer by stanbon(75887)

Question 142112: Graph the inequality.
4x + 5y <_ 20 (of course the _ goes under the <)
Can someone please help me with this one?
Click here to see answer by stanbon(75887)

Question 142111: please help me graph x^2+3x=18
Click here to see answer by nabla(475)

Question 142115: How do I determine the slope of a line while looking at a line on a graph?? It says m = ??
Just take the 2 points from y and x and put it parenthsis?? y comes first correct? Am I even close?
Click here to see answer by stanbon(75887)

Question 142118: 0.4x + 3 <_ 1.2x-6
Will someone please help me.
Click here to see answer by Earlsdon(6294)

Question 142116: Soybean meal is 16% protein; cornmeal is 8% protein. How many pounds of each should be mixed together in order to get 320-lb. mixture with 15% protein?
How many pounds of the cornmeal should be in the cornmeal mixture?
How many pounds of the soybean meal should be in the mixture?
HELP I hate word problems!!!! PLEASE!
Click here to see answer by scott8148(6628)

Question 142117: Graph the eqquation and identify the y-intercept.
y + x = -8
HELP PLEASE!!!!!!
Click here to see answer by josmiceli(19441)

Question 142348: In the equation : x^a - x^b = z , where 'x' & 'z' is a positive integer, where a>b and 'a' & 'b' are positive integers. Can we find the value of 'a' & 'b' ? when the value of 'z' and 'x' is given. Is there any method. For example given eqn 2^a - 2^b = 32512. Here can we find that a=15 and b=8.
For example given eqn 3^a - 3^b = 6318. Here can we find that a=8 and b=5.
I need method to find a and b. This is the question of finding two variables in an equation. Please help me to know this. If possible please find URL where solution is present.(FROM SHIVA)
Click here to see answer by scott8148(6628)

Question 142368: A man walks at a pace of 3 miles per hour. After 2 hours he stops for a rest. Let t be time AFTER the rest. Let d be the TOTAL distance traveled since he started. Write an equation linking d and t.
Click here to see answer by scott8148(6628)

Question 142421: i need help with factoring questions such as
Click here to see answer by luckycarebear4(1)

Question 142445: what is the answer to -2x2 + 5x = 0
15c2 - 12c = 48

m2=4m - 4
Click here to see answer by checkley77(12844)

Question 142372: A high school class wants to raise money by recycling newspapers. The class decided to rent a truck at a cost of $150 for the week. The market price for recycled newspapers is $15 per ton. Write an equation representing the amount of money the class will make based on the number of tons of newspapers collected...
15*x-150= T
Click here to see answer by jojo14344(1513)

Question 142537: I need help!!! My problem is I must solve this equation by completing the square!!! The equation is r2-2r-35=0!!! Can you please help me!!!
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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