Questions on Algebra: Systems of Linear Equations answered by real tutors!

Tutors Answer Your Questions about Linear-systems (FREE)

Question 45081: Solve the following system of linear equation.
y=2x+1
x+y=-2
Click here to see answer by checkley71(8403)

Question 44967: 2x-3y+z=7
x+2y-3z=7
-x+4y+3z=5

solve in three variables using cramer's rule
thank you
Click here to see answer by checkley71(8403)

Question 45372: Could you help with this problem:
1/3S + 7/9 = 4/3s
So far what I have done is:
Multiplied both sides by 9 to get 9(1)/3s + 9(7)/9 + 9(4)3s
Then I get 3 * s + 7 = 3 * 4 * s
Which is 3 * s + 7 = 12s
Then I have subtracted 3s from both sides but I'm not sure about these steps.
I get stuck here. Can you help?
Click here to see answer by stanbon(75887)

Question 45375: Hello !!
Please help me with the following problem whish for some reason has driven me mad with anguish over my inability tonight to represent it in the propoer mathematical form (linear equation system). Please show me how you work out this problem.
"A glass of milk supplies 0.1 mg of iron and 8.5 mg of protein. A quarter pound of lean meat provides 3.4 mg of iron and 22 g of protein. If a person on a special diet is to have 7.1 mg of iron and 69.5 g of protein, how many glasses of milk and how many quarter-pound servings of meat will provide this?"
THANK YOU LIFE-SAVERS !!
Alex
Click here to see answer by rapaljer(4671)

Question 45443: I would like help with this problem:
1/2q - 6 = 1/5q
What I have worked so far is:
1/2q - 6 - 1/5q = 1/5q - 1/5q
Could someone help me from here?
Click here to see answer by tutorcecilia(2152)

Question 45449: Please help me solve this problem:
0.10x + 0.08(1-x) = 0.0948
This is what I tried:
0.10x + 0.08(1-x) = 0.0948
.10x + .08 - .08x = .0948
.02x = 0.0148
x = 0.74

Click here to see answer by Fermat(136)

Question 45539: Hello!
Would anyone please help with the following word-problem that requires the proper linear equation setup:
"A nurse has two solutions that contain different concentrations of a certain medication. One is a 10% concentration and the other is 5% concentration. How many cubic centimeters of each should she mix to obtain 20 cubic centimeters of an 8% solution?"
THANK YOU.
Alex
Click here to see answer by Nate(3500)

Question 45538: Hello!
Would anyone please help with the following word-problem that requires the proper linear equation setup:
"A nurse has two solutions that contain different concentrations of a certain medication. One is a 10% concentration and the other is 5% concentration. How many cubic centimeters of each should she mix to obtain 20 cubic centimeters of an 8% solution?"
THANK YOU.
Alex
Click here to see answer by Nate(3500)

Question 45620: Solve the following system of linear equations by the substitution method. Clearly state the solution.
3x-5y=4
y=3/4x-2

Click here to see answer by Nate(3500)

Question 45618: (1) Write an equation for the following statement and solve it:
�The length of a rectangle is 1 yard shorter than twice the width, and the perimeter is 298 yards. What is the value of the width and length?�

Click here to see answer by Nate(3500)

Question 45946: I have to solve this system.
-2(x+y)-3=5x+3y-10
-3y-(x+2)=3y-5x+5
I have worked it several times and keep getting different answers.
Please help!
Click here to see answer by venugopalramana(3286)

Question 46104: An Investment is worth $ 3432 in 1991. By 1995 it as grown to $ 4132. Let y be the value of the investment in the year x, where x = 0 represents 1991. Write a linear equation that models the value of the investment in the year x.
I am to solve and assume that the exercise describes a linear relationship.
Click here to see answer by Nate(3500)

Question 46280: Without graphing, determine whether the graphs of the equations are identical lines, parallel lines, or lines that intersecting at a single point.
y-5x= 2
5y = 25x + 10
Click here to see answer by Nate(3500)

Question 46281: Without graphing, determine whether the system has one solution, no solution, or an infinite number of solutions.
6x - y = 14
x + 3y = 15
thank you
Click here to see answer by Nate(3500)

Question 46678: I have a problem that I can not complete 3/10x + 9/14x^2 The answer I was given is 3(7x + 15)/70x^2 How the heck did they get that???? Can you help??
By the way x^2= x squared
Click here to see answer by Earlsdon(6294)

Question 46826: this problem is from the beginning algebra book
I need help to graph this linear equation I have tried it own my own but can't seem to solve can you help me.
3x-4y<12
Click here to see answer by adamchapman(301)

Question 46934: What is the equation of the line with y-intercept 7 and x-intercept 5?
Click here to see answer by fractalier(6550)

Question 46997: Solve equation for ordered pair
x^2+y=4
2x+y=1

Click here to see answer by mathchemprofessor(65)

Question 47165: A math class has 29 students. There are 3 more boys than girls. How many boys and girls are there?
Click here to see answer by Nate(3500)

Question 47167: The length of a rectangle is 3 times it's width. The perimeter is 48. Find the length and width
Click here to see answer by adamchapman(301)

Question 47163: The sum of two numbers is 137. The difference between the numbers is 29. What are the two numbers?
Click here to see answer by adamchapman(301)

Question 47166: Two pieces of rope measure 25 feet. One piece is 3 feet more than the other. What are the lengths of the two pieces?
Click here to see answer by adamchapman(301)

Question 47402: Hi,
I would really appreciate some help with this question:
A painter can prepare and paint a room in 10 hours. His son requires 18 hours to do the same job. How long will it take to prepare and paint the room working together?
Thank you,
Louis
Click here to see answer by Earlsdon(6294)

Question 47538: 3x^2+11x=4. I was told the answer was -3 2/3. I am stuck. I don't see how that was gotten.
Click here to see answer by stanbon(75887)

Question 47460: Hi,
I hope you can help.
Here's my formula to which I want to find the value of x
(x* 1.4) - x = 10
Please re-write the formula starting with "x = "
Many thanks
Matt Webb
Click here to see answer by tsmith5651(7)

Question 47559: Looking at the points (3,0) (0,2) on a line (graph) the slope is -2/3 and the value of y when x=2 is ______.
Click here to see answer by stanbon(75887)

Question 47612: Please help!
If u=x-2 is an equation representing a line on a graph, which direction is the line moving, and what is the slope?
a. up and to the left, m=2
b. up and to the right, m=1
c. upand to the left, m=1
Thank you!
Click here to see answer by checkley71(8403)

Question 47615: please help!
2/3(x+9) is less than or equal to 1/3(2x+12)
A. X is less than or equal to 6
B. x= all real numbers
C. X has no solution
Thank you!
Click here to see answer by Earlsdon(6294)

Question 47613: how do you type the less than/equal to sign on the computer? anyway, here's the question. Hope you can understand:
solve for x: 1/5x - 2 (is greater than or equal to) 3/4x +5
Click here to see answer by stanbon(75887)

Question 47164: The length of a rectangle is twice the width. The perimeter is 36 units. What are the length and width?
Click here to see answer by mszlmb(115)

Question 47693: Please help! I'm stuck!
2x - 3 >= 1/2(4x+4)
A. x=1
B. X= all real numbers
C. x has no solution.
Thank you!
Click here to see answer by aaaaaaaa(138)

Question 47818: SUBSTITUTION METHOD 3X - 3Y = 2 EQUATION 1
X + 2 = 3Y EQUATION 2
Click here to see answer by venugopalramana(3286)

Question 47817: The sum of the digits of a 2 digit no. is 9, when the digits are reversed the new no. is 27 more than the original no. Find the no.
Click here to see answer by venugopalramana(3286)

Question 47914: I'm having a hard time with this problem. I'm not sure if I'm doing this right.
It says solve the system by the elimination method
7x+5y=42
4x-3y=24
doing this I came up with this 28x+20y=168
28x-21y=168
some how I end up with -1. I'm trying to cancell out the x but the 168 is bothering me, it doesnt look right. Please help me
Click here to see answer by 1980.vikas(7)

Question 49215: how I can write it x>6 in interval notation. Graph each interval.
Click here to see answer by tutorcecilia(2152)

Question 49302: In this one I also have no clue to both how to do it or what types of problems these are.

Ive tried and tried and still couldnt rember any of this

Click here to see answer by AnlytcPhil(1806)

Question 49352: Find values for m and b in the following system so that the solution to the system is (-3,4)
5x + 7y = b
mx + y =22
Click here to see answer by Nate(3500)

Question 49447: Can someone help me on this problem?
5x + 8 + 3x - x + 5 = 6x -3
Thanks,
S her
Click here to see answer by checkley71(8403)

Question 49536: I honestly don't even know where to start. Any advice would be awesome!!
Solve any way you can:
3x - y - 2z = 11
x � 2y + 3z = 12
x + y - 2z = 5
I look forward to your thoughts!!
Andrea
Click here to see answer by longjonsilver(2297)

Question 49625: The area of a trapezoid is 63 square inches. One base is 9 in. long and the other is 10 in long. Find the height of the trapezoid.
Click here to see answer by checkley71(8403)

Question 49620: Suppose that you have scores of 86,93,80,and 88 on four exams in your algebra class. What score will you need on the fifth exam to have an average of 90?
Click here to see answer by Earlsdon(6294)

Question 49622: A jeweler paid 1455 for a watch. He wants to price the watch for sale so that he can give the customer a 25% discount on the selling price and still make a profit of 30% on his cost. What selling price should he mark for the watch?
Click here to see answer by checkley71(8403)

Question 49587: 2x-4y=7
4x+2y=9
Solve the system by addition. I used the solver but it didn't make sense to me. Can you explain this in more detail please.
Click here to see answer by checkley71(8403)

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