Questions on Algebra: Quadratic Equation answered by real tutors!

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Question 81494: Solve the following system by graphing
2x-y=4
2x-y=6
Click here to see answer by tutorcecilia(2152)

Question 81578: show a complete solution
find the exact length of the side of a square whose diagonal is 3 ft. not sure how to set this up please help with step by step
Click here to see answer by tutorcecilia(2152)

Question 81612: I am stuck on this problem, can you help me out please? Thank you!
2) For the function y = x2 - 4x - 5, perform the following tasks:
a) Put the function in the form y = a(x - h)2 + k.
Answer:
Show work in this space

b) What is the equation for the line of symmetry for the graph of this function?
Answer: 0

c) Graph the function using the equation in part a. Explain why it is not necessary to plot points to graph when using y = a (x � h)2 + k.
Show graph here.

Explanation of graphing.

d) In your own words, describe how this graph compares to the graph of y = x2?

Click here to see answer by stanbon(75887)

Question 81539: Find the slope of any line perpendicular to the line through points (3, 12) and (5, 4).
Click here to see answer by checkley75(3666)

Question 81461: y=-x-2x. how do i slove this problem? how do i graph it?
Click here to see answer by checkley75(3666)

Question 81640: The sum of two numbers is 112. The second is 7 more than 4 times the first. What are the two numbers?
Click here to see answer by tutorcecilia(2152)

Question 81641: Lane invested $14,000, part at 15% and part at 2%. If the total interest at the end of the year is $1,060, how much did she invest at 15%?
Click here to see answer by checkley75(3666)

Question 81714: Given g(x) = 3x � 3, find g(2a).
Answer: g(2a) =

Click here to see answer by rapaljer(4671)

Question 81726: Given f(x) = x2 + x � 9, find f(0).
Answer: f(0) =

Click here to see answer by rapaljer(4671)

Question 81723: Given f(x) = 3x � 4, find f(�2).
Answer: f(�2) =

Click here to see answer by rapaljer(4671)

Question 81729: The sum of two numbers is 114. The second is 6 more than 5 times the first. What are the two numbers?
Answer:
One number is
And the other number is

Click here to see answer by Earlsdon(6294)

Question 81742: Adult tickets for a play cost $10 and child tickets cost $3. If there were 25 people at a performance and the theater collected $110 from ticket sales, how many adults and how many children attended the play?
Answer:
___________ adults attended the play
___________ children attended the play

Click here to see answer by bucky(2189)

Question 81721: Adult tickets for a play cost $10 and child tickets cost $3. If there were 25 people at a performance and the theater collected $110 from ticket sales, how many adults and how many children attended the play?
Answer:
___________ adults attended the play
___________ children attended the play

Click here to see answer by bucky(2189)

Question 81749: suppose a baseball is shot up from the ground straight up with an initial velocity of 64 feet per second. a function canbe created by expressing distance above the ground,s,as a function of time,t. this function is s=-16t^2+vot+so.
>16 represents 1/2g, the gravitational pull due to gravity(measured in feet per second^2)
>vo is the initial velcoity(how hard do you throw a object, measured in feet per second)
>So is the initial distance above ground(in feet). if you are standing on the ground, then So=0
-what is the function that describes this problem
-the ball will be how high above ground after 1 second
-how long will it take to hit ground
-what is the max height of the ball? what time will the max height be attained?
Click here to see answer by bucky(2189)

Question 81709: Solve. 9x^2 = 14
thank you
Click here to see answer by Edwin McCravy(20054)

Question 81753: Solve the system by graphing.
x + y = 4
�x + y = 2

Click here to see answer by bucky(2189)

Question 81771: Problem
Find three consecutive integers such that the sum of their squares is 77.
This is what I have, but not sure.
x^2 + x^2 + x^2 = 77 I don't know where to go from here. Thank you for your help.
Click here to see answer by jim_thompson5910(35256)

Question 81773: I need to figure out how to put this function y=x^2-4x-5 into this form
y=a(x-h)^2+k
Click here to see answer by dolly(163)

Question 81780: Find the exact length of the side of a square whose diagonal is 3 feet.
This is what I have.
x^2 + x^2 = (x + 3)^2
x^2 + 4x + 9
x^2 - 4x - 9 = 0
x= 4 plus/minus sqrt 39 - 9(1)(-4)/2(1)
6 + 9 sqrt (2)/2
= 6 + 3 sqrt (2)
Would appreciate any help with this question. Thank you
Click here to see answer by jim_thompson5910(35256)

Question 81774: Problem
In a playoff game the ball was carried by either Anderson or Brown on 21 plays. Anderson gained 36 yards, and Brown gained 54 yards. If Brown averaged twice as many yards per carry as Anderson, then on how many plays did Anderson carry the ball?
I think I need to set it up as follows, but am not sure
2(36/x)= 54/21-x
Thank you for your help
Click here to see answer by stanbon(75887)

Question 81806: Problem
In 1981 Vladimir Poliakov set a world record of 19ft3/4in for the pole vault. To reach that height, Poliakov obtained a speed of approximately 36 ft per second on the runway. The formula h = -16t + 36t gives his height t seconds after leaving the ground. Use the formula to find the exact values of t for which his height is 18ft.
This is what I have
18 = -16t + 36t
18 = 20t
20t/20 = 18/20
t = 9/10
Not sure if I did this right, would appreciate your input. Thank you
Click here to see answer by rapaljer(4671)

Question 81812: hi i need help with this it is due tomm on mothers day and i cant figure it out.
A home-based company produces both hand-knitted scarves and sweaters. The scarves take 2 hours of labor to produce, and the sweaters take 14 hours. The labor available is limited to 40 hours per week, and the total production capacity is 5 items per week. Write a system of inequalities representing this situation, where x is the number of scarves and y is the number of sweaters. Then graph the system of inequalities.
Click here to see answer by ankor@dixie-net.com(22740)

Question 81852: The question is not from the book
You have a square with 20 ft. sides, two people at opposite corners. How far apart are they?
Not sure how to set this up, Thank you for your help.
Click here to see answer by stanbon(75887)

Question 81337: please check this for me?
7x^2+18-9
x=-b+-sqrt/2a
x=-18+-sqrt/2*7
x=(-18+24)/2*7
x=6/14=3/7
x=-42/14=-3
x=-3,7
Click here to see answer by vertciel(183)

Question 81862: 2x(x+3)= -1
Click here to see answer by vertciel(183)

Question 81864: 9x^2-120x-81=0
How is this worked out?
Click here to see answer by checkley75(3666)

Question 81847: please solve this equation its urgent------------ (x^4)-(5*x^2)+4
Click here to see answer by checkley75(3666)

Question 81861: (a-2)(a+4)= 2a(a-3)
Click here to see answer by checkley75(3666)

Question 81717: The difference of two numbers is 47. The second is 1 less than 3 times the first. What are the two numbers?
Answer:X+Y=47, X=47-Y
Y=3X-1 NOW SUBSTITUTE (47-Y) FOR X IN THE THIS EQUATION & SOLVE FOR Y
Y=3(47-Y)-1, Y=141-3Y-1, Y+3Y=140, 4Y=140, Y=140/4, Y=35ANSWER.
X+35=47, X=47-35, X=12 ANSWER.
One number is: 12
And the other number is: 35

Click here to see answer by checkley75(3666)

Question 81891: Everyone in my family has tried to answer this worksheet from school. Does it need to be solved before graphing? Would appreciate your help with this problem. Thanks!
A rocket is launched from atop a 78-foot cliff with an initial velocity of 152 feet per second. the height of the rocket t seconds after launch is given by the equation h=-16t^2 + 152t + 78. Graph the equation to find out how long after the rocket is launched it will hit the ground. Estimate the answer to the nearest tenth of a second.
Click here to see answer by Earlsdon(6294)

Question 81964: Graph x = 3.
Click here to see answer by bucky(2189)

Question 81962: . Graph y = �1
Click here to see answer by bucky(2189)

Question 81961: Which of the ordered pairs (3, 1), (0, �4), (�4, 0), (�3, �7)are solutions for the equation x � y = 4?
Click here to see answer by bucky(2189)

Question 81963: Plot the point with coordinates (�4, 3).
Click here to see answer by lilhoopstar80(1)

Question 81963: Plot the point with coordinates (�4, 3).
Click here to see answer by Edwin McCravy(20054)

Question 81958: The sum of a number and �16 is 3. Find the number.
Click here to see answer by neta(14)

Question 81958: The sum of a number and �16 is 3. Find the number.
Click here to see answer by bucky(2189)

Question 81957: A principal of $5000 was invested in a savings account for 4 years. If the interest earned for the period was $400, what was the interest rate?
Click here to see answer by neta(14)

Question 81936: This is a word problem.
#116 Time of flight. Use the information from exercise 115 to determine how long Johnson was in the air. For how long was he more than 14ft in the air.
Exersice 115
For 1989 and 1990 Dave Johnson had the highest decathlon score in the world. When Johnson reached a speed of 32 ft/sec on the pole vault runway, his height above the ground t seconds after leaving the ground was given by h=-16t^2+32t.
How do I solve Problem 116? Please help
Click here to see answer by ankor@dixie-net.com(22740)

Question 82034: Find the value of r in the quadratic equation:
r (to the 2nd power) - 7r - 8 = 0.

Click here to see answer by jim_thompson5910(35256)

Question 82085: Solve using the quadratic formula.
x^2-5x-1=-7
Click here to see answer by checkley75(3666)

Question 82104: I am REALLY struggling with this
how do i graph the inequality
Y>/1?
Click here to see answer by stanbon(75887)

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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, 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