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Question 686974: I don't understand how to find the factors for this equation : 4x to the second power + 10x + 4=
The answer is 2(2x to the second power + 5x + 2)
= 2(2x + 1)(x+2)
I understand the first problem, but I don't see the 10x in the final solution. I don't understand why this is the answer.

Click here to see answer by Stitch(470)

Question 687016: Two of the top grossing concert tours were by a jazz band and a rock band. Together, the two tours visited 172 cities. The jazz band visited 94 cities more than the rock band.
How many cities did each group visit.
Click here to see answer by lynnlo(4176)

Question 687304: Please help me solve this: 3x-y=11 x+y=5 in elimination and substitution method.
Click here to see answer by stanbon(75887)

Question 687341:
Click here to see answer by lizterry(3)

Question 687661: Solve and check the linear equation.
0.08(50) + 0.40x = 0.20(50 + x)
Click here to see answer by MathLover1(20850)

Question 687692: Sketch the region the region that corresponds to each inequality. Then use your graph to determine if (3,-2)is a solution to the inequality and explain :
A) X- 3Y >/ 3
B) X /< -2
>/ MEANING GREATER THAN OR EQUAL TO
/< LESS THAN OR EQUAL TO
Click here to see answer by stanbon(75887)

Question 687688: Is c=0.05m+20 a linear equation?
Click here to see answer by MRperkins(300)

Question 687726: Express the following as single fraction in it's simplest form.
3x/4+2(1-3x)/5
Click here to see answer by josh_jordan(263)

Question 687858: A is 20years older than b.5years ago,a was 3 times as old as b.find their present ages.

Click here to see answer by stanbon(75887)

Question 687997: Hi I need answers for this problem.
3a+4b=2
-3a+b=23
Click here to see answer by lwsshak3(11628)

Question 688078: 2x+3(5x -7) = 4x+5
Click here to see answer by rfer(16322)

Question 688223: graph and use the slope & y intercept
x+5y=10
Click here to see answer by stanbon(75887)

Question 688349: Please help me solve this system by substitution? { 2x - y = 4
{ y = 2x - 4
Click here to see answer by MathLover1(20850)

Question 688466: Sean is sending a text message to a friend.The function y=6 - x/5 represents the number of words y the message can hold after he types x words.Find the zero and explain what it means in the context of this situation.
Click here to see answer by ReadingBoosters(3246)

Question 688640: I am having trouble using the substitute method to solve the simultaneous equation:
y=5x+3
y=2x-9
I have tried to substitute variable y of the second equation into first:
2x-9=5x+3
And then solve for x, but I'm not getting the right answer?
Please could you explain what I am doing wrong and how I should be doing it.
Click here to see answer by ReadingBoosters(3246)

Question 688927: how do you solve 2x-3y=-1 when y=x-1
Click here to see answer by jim_thompson5910(35256)

Question 689000: Can you help me ?
x+y=525
4x+6y=2876
Click here to see answer by ReadingBoosters(3246)

Question 689494: -4.9r(2) +t +350
Click here to see answer by lynnlo(4176)

Question 689486: what is the value of x in the equation 4(2x+1)=27+3(2x-5)
Click here to see answer by checkley79(3341)

Question 689340: Please help me solve this question:
If a car traveled 5kilometer an hour faster it would take one hour less to travel 210 km. what is the speed of the car and what time does it take?
Thank you,
Click here to see answer by ankor@dixie-net.com(22740)

Question 689989: For f(x)=x^2+3x and g(x)=x-2 find f(g(x)).
Click here to see answer by stanbon(75887)

Question 690050: -1n - 24 = 5 - n
Click here to see answer by stanbon(75887)

Question 691201: I need help solving this equation using the elimination method:
x+6y=79
x-4y=-41
Click here to see answer by ankor@dixie-net.com(22740)

Question 691201: I need help solving this equation using the elimination method:
x+6y=79
x-4y=-41
Click here to see answer by ReadingBoosters(3246)

Question 691380: Plz I don't get this a girl is b years old and her sister Is x years older than she is what will their average age be in 10 years time

Click here to see answer by Alan3354(69443)

Question 691410: The sum of the digits of a two digit number is 1. The number formed by reversing the number is 4 less than 5 times the number. Find the original number?
Can you please help me out with this question I really don't understand? thanks in advance.
Click here to see answer by ankor@dixie-net.com(22740)

Question 691610: Determin whether (6,11) is a solution of y=13x-12
Could you show me how to work this problem out
Click here to see answer by josmiceli(19441)

Question 692051: I don't know how solve this system:
x-y= -11
-x+y= -14
Click here to see answer by KMST(5328)

Question 692247: Solve the system. If the system has infinitely many solutions, write the solution set with x arbitrary.
6x+5y=7
12x+10y=5
Click here to see answer by Alan3354(69443)

Question 692320: Can I please get help on this question? Lin paid 42 cents for a pencil and two erasers. Kim paid 91 cents for five pencils and three erasers? What were the prices of pencils and erasers?
Click here to see answer by MathTherapy(10552)

Question 692384: I need with a Linear Equations Word problem in Algebra 1. Here it is:
One pipe can be used to fill a tank in 48 min and another can be used to fill it in 1 hour and 12 min. How long will it take to fill the tank if both pipes are used.
Click here to see answer by ankor@dixie-net.com(22740)

Question 692484: "what is x+2y=5 and 3x-2y=7?"
Click here to see answer by checkley79(3341)

Question 692447: how do you solve 8x-5y=9
y=2x-4
Click here to see answer by lynnlo(4176)

Question 692541: Im Very Confused on how to find x and y intercepts , i try my best to work them out but i need help with graphing them. I cannot understand how to graph 7x-3y=6
Click here to see answer by Alan3354(69443)

Question 692688: Driving from Tulsa to Detroit, Dean's average speed was 50 mph. If he had averaged 60 mph instead, this would have decreased the drive time by 3hr. How many miles was the drive from Tulsa to Detroit?
note: let x = the distance from Tulsa to Detroit, do not use other variables. Answer part a and b.
a) Fill in chart:
R ----- T ----- D
50
60
b) Write and solve a correct equation that could be used to solve for x.

What I've tried:

Chart:
r: 50 t: x/50 d: x
r: 60 t: x/60 - 3 d: x
my equation:
x/50 = x/60 -3
(lcd = 300)
300(x/50)=300(x/60)- 300(3)
6x = 5x - 900
x = -900
my answer: x =-900
I don't think it's right due to the negative answer but it's the best I can come up with.
Click here to see answer by MathTherapy(10552)

Question 692825: equation of a line passing through (-3,-2) and (1,-2) in the form of y=mx+b
Click here to see answer by Alan3354(69443)

Question 693032: What is the equation of the line that passes through the points(-4,1) and (-4,6)?
Click here to see answer by jim_thompson5910(35256)

Question 693091: how to graphing by shading when it is y < 7 ?
Click here to see answer by jim_thompson5910(35256)

Question 693295: how many solutions the linear system has. this is for my algebra 2 class.
4x-2y=8
2x-y=7

Click here to see answer by stanbon(75887)

Question 693618: how can i solve y=1/2x + 3 -x+ 2y = 7
Click here to see answer by ReadingBoosters(3246)

Question 693656: use substitution to solve the system x - 2y = 1 and 6x - 5y = 20

Click here to see answer by ReadingBoosters(3246)

Question 693696: I have tried to solve this problem but when I check it I'm wrong! I'm stumped and don't know what to do here is my work the name of my lesson is solving linear equations using multiplication first:
-2x-5y= 9 -6x - 15y = 27
3x+11y= 4 -6x - 22y = 8
+_____________
7y = 19
y = here is where I got stumped what am I doing wrong???
Click here to see answer by ReadingBoosters(3246)

Question 693720: David has been working for his company since 1990. Each year he gets a $2100 raise, in 1998 he earned one and a half times as much as he earned in 1990.
Write an equation in the form of y=mx+b that models David's salary y in terms of number of years x since he started working there. What was his salary in 1998? How much will he earn in 2005?
Click here to see answer by stanbon(75887)

Question 693687: Solve for "c" using the substitution method.
5x-7y=c
-15x+21y=9
Click here to see answer by ankor@dixie-net.com(22740)

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, 3871..3915, 3916..3960, 3961..4005, 4006..4050, 4051..4095, 4096..4140, 4141..4185, 4186..4230, 4231..4275, 4276..4320, 4321..4365, 4366..4410, 4411..4455, 4456..4500, 4501..4545, 4546..4590, 4591..4635, 4636..4680, 4681..4725, 4726..4770, 4771..4815, 4816..4860, 4861..4905, 4906..4950, 4951..4995, 4996..5040, 5041..5085, 5086..5130, 5131..5175, 5176..5220, 5221..5265, 5266..5310, 5311..5355, 5356..5400, 5401..5445, 5446..5490, 5491..5535, 5536..5580, 5581..5625, 5626..5670, 5671..5715, 5716..5760, 5761..5805, 5806..5850, 5851..5895, 5896..5940, 5941..5985, 5986..6030, 6031..6075, 6076..6120, 6121..6165, 6166..6210, 6211..6255, 6256..6300, 6301..6345, 6346..6390, 6391..6435, 6436..6480, 6481..6525, 6526..6570, 6571..6615, 6616..6660, 6661..6705, 6706..6750, 6751..6795, 6796..6840, 6841..6885, 6886..6930, 6931..6975, 6976..7020, 7021..7065, 7066..7110, 7111..7155, 7156..7200, 7201..7245, 7246..7290, 7291..7335, 7336..7380, 7381..7425, 7426..7470, 7471..7515, 7516..7560, 7561..7605, 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, 11161..11205, 11206..11250, 11251..11295, 11296..11340, 11341..11385, 11386..11430, 11431..11475, 11476..11520, 11521..11565, 11566..11610, 11611..11655, 11656..11700, 11701..11745, 11746..11790, 11791..11835, 11836..11880, 11881..11925, 11926..11970, 11971..12015, 12016..12060, 12061..12105, 12106..12150, 12151..12195, 12196..12240, 12241..12285, 12286..12330, 12331..12375, 12376..12420, 12421..12465, 12466..12510, 12511..12555, 12556..12600, 12601..12645, 12646..12690, 12691..12735, 12736..12780, 12781..12825, 12826..12870, 12871..12915, 12916..12960, 12961..13005, 13006..13050, 13051..13095, 13096..13140, 13141..13185, 13186..13230, 13231..13275, 13276..13320, 13321..13365, 13366..13410, 13411..13455, 13456..13500, 13501..13545, 13546..13590, 13591..13635, 13636..13680, 13681..13725, 13726..13770, 13771..13815, 13816..13860, 13861..13905, 13906..13950, 13951..13995, 13996..14040, 14041..14085, 14086..14130, 14131..14175, 14176..14220, 14221..14265, 14266..14310, 14311..14355, 14356..14400, 14401..14445, 14446..14490, 14491..14535, 14536..14580, 14581..14625, 14626..14670, 14671..14715, 14716..14760, 14761..14805, 14806..14850, 14851..14895, 14896..14940, 14941..14985, 14986..15030, 15031..15075, 15076..15120, 15121..15165, 15166..15210, 15211..15255, 15256..15300, 15301..15345, 15346..15390, 15391..15435, 15436..15480, 15481..15525, 15526..15570, 15571..15615, 15616..15660, 15661..15705, 15706..15750, 15751..15795, 15796..15840, 15841..15885, 15886..15930, 15931..15975, 15976..16020, 16021..16065, 16066..16110, 16111..16155, 16156..16200, 16201..16245, 16246..16290, 16291..16335, 16336..16380, 16381..16425, 16426..16470, 16471..16515