Questions on Algebra: Expressions involving variables, substitution answered by real tutors!

Tutors Answer Your Questions about Expressions-with-variables (FREE)

Question 124743: Please simplify this:
1/a-b + 4/b-a - 8/a+b - 11a-5b/b^2-a^2
I have no idea where to begin. Please help--Thanks.
Click here to see answer by stanbon(57282)

Question 124972: i need to be shown the work to get the answer to this problem.
what is the value of this rational expression when x = 3?
x-1
_____
(x+1)(x-5)

Click here to see answer by chitra(359)

Question 125047: Evaluate. | –12 | – | –10|
Click here to see answer by stanbon(57282)

Question 125041: 2x+y=28
Click here to see answer by checkley71(8403)

Question 125029: This entire lesson revolves around the 3 step principle of:
assigning a variable
writing a sentence placing the demands on the variable
solving the equation.
We need a usable formula that will work in all these cases!
THANK YOU!!!
Here's the question:
Two years ago a father was four times as old as his son. Three years from now the father will be only three times as old as the son. How old is each now?
Click here to see answer by edjones(7569)

Question 125113: How do you know if an expression has infinitely many solutions?
Click here to see answer by checkley71(8403)

Question 125103: Will you help me with substitution?
y=4x
3x-y=1
and
-3x+5y=81
2x+y=24
Click here to see answer by ilana(307)

Question 125160: The sum of three numbers is 180. Two of the numbers are the same, and each of them is one third of the greatest number. What is the least number?
Click here to see answer by stanbon(57282)

Question 125212: You have a front row ticket that = $4.00 less than 2 times the lawn ticket.
2 front row tickets plus 5 lawn tickets = $ 100.00.
What is the cost of each type of ticket?
Click here to see answer by josmiceli(9664)

Question 125300: I need you to solve each system by using substitution.
6. y= -3x - 6
y= x-4
7. y= 5x + 8
y= -10x + 3
8.y= -4x - 8
y= 1/4x + 4
9.y= 6x - 4
y= -2x + 28
10. y= 2/5x - 3
y= 2x - 18
11. y= x - 2
2x + 2y =4
12.y= 3x - 27
y= 4x + 10y = 120
13.y= 3x - 6y =30
-y= -6x +34

Click here to see answer by checkley71(8403)

Question 125597: Solve by elimination:
1.8x + 11y= 20
5x - 11y= -59
2. 2x + 18y= -9
4x + 18y= -27
3. 20x + 3y= 20
-20x + 5y= 60
4. 3x - 10y= -25
4x + 40y= 20
5. 7x + 15y= 32
x - 3y= 20
6. x - 8y= 18
-16 + 16y= -8
7. 24x + 2y= 52
6x - 3y= -36
8. 88x - 5y=39
-8 + 3y= -1
9. 2x + 4y= 8
5x + y= -7
10. 3x + 2y= -9
-10x + 5y= -26
11. 4x + 5y= 15
6x - 4y= 11
12. 3x - 2y= 10
2x + 3y= -2
13. -2x + 5y= 20
3x - 7y= -26
14. 10x + 8y= 2
8x + 6y= 1
15. 9x + 5y= 34
8x - 2y= -2

Click here to see answer by jim_thompson5910(28536)

Question 125626: IF X=Y-1 AND Y=4-2X; SOLVING BY THE SUBSTUTION METHOD; WHAT ARE THE VALUES FOR FOR X AND Y?
Click here to see answer by SoOoDumb(14)

Question 125664: I am a teacher/mom trying to help my 9th grade son. I have redone 3 different problems about 3 times each. This is one of them. Help!
Click here to see answer by Fombitz(13828)

Question 125659: How do you substitute variables if you are doing a double variable questions?
Click here to see answer by benni1013(197)

Question 125647: solve for the indicated variable: (x-2y+xz)/(x-z)=4y SOLVE FOR X can you give me a step by step guide to solving this, because i am completely lost
Click here to see answer by jim_thompson5910(28536)

Question 125724: 5(x+2) + 3(7+x)
Click here to see answer by jim_thompson5910(28536)

Question 125662: Write the following as an algebraic expression then simplify
a) The sum of three consecutive integers if x is the first consectutive integers.
b)The perimeter of a square with side length 3x +1.
Click here to see answer by ankor@dixie-net.com(15645)

Question 125980: okay the question is if f(x)=x squared+3x-2 and it says that F(5v) Im supposed to find each value
This is what I got and Im pretty sure it's wrong
5v squared+13v=18v to the 3rd power
Thanks for any and all help

Click here to see answer by Earlsdon(6287)

Question 126002: 3a - 2b =21
a + 3b = -4
what is the value of each variable (a and b)?
Click here to see answer by MathLover1(6625)

Question 126070: How do you get the answer to 2x+7y=3
x=1-4y
Click here to see answer by jim_thompson5910(28536)

Question 126070: How do you get the answer to 2x+7y=3
x=1-4y
Click here to see answer by stanbon(57282)

Question 126200: a a+b
- + ---
b a-b
_______
a a-b
- - ---
b a+b
In other terms:
[(a/b)+(a+b)/(a/b)]/[(a/b)-(a-b)/(a+b)]

I tried to multiply both denominator and numerator by [b(a+b)(a-b)}\] but that didnt seem to work for me.
Click here to see answer by stanbon(57282)

Question 126180: how do you solve y=x-2 y=4x+1
Click here to see answer by ankor@dixie-net.com(15645)

Question 126247: the difference of 12 and a number
Click here to see answer by checkley71(8403)

Question 126255: X+2/X+6 = X-1/X+5
Click here to see answer by MathLover1(6625)

Question 126410: Ron can paint a room in 6 hours working alone. If his son, Jason, helps him, the job takes 4 hours. How long would it take Jason to do the job alone?
Click here to see answer by stanbon(57282)

Question 126412: Ron Wood can paint a room in 6 hr working alone. If his son, Jason, helps him, the job takes 4 hr. How long would it take Jason to do the job if he worked alone?
Click here to see answer by ankor@dixie-net.com(15645)

Question 126499: Please show me how to solve this problem ( it was a homework problem (1 complete problem) and I didn't know where to start). thanks!
200 Students
70 Students take English class
54 Students take Math class
45 Students take Social Studies
28 Students take English and Math
19 Students take English and Scial Studies
15 Students take Math and Scial Studies
10 Students take English, Math and Social Studies
1.) How many students take English
2.) How many Students take math only
3.) How many Students take English, social studies but not math
4.) How many students take math and social studies but not English class
5.) How many do not take any class.
Click here to see answer by solver91311(16872)

Question 126497: Please show me how to solve this problem ( it was a homework problem (1 complete problem) and I didn't know where to start). thanks!
200 Students
70 Students take English class
54 Students take Math class
45 Students take Social Studies
28 Students take English and Math
19 Students take English and Scial Studies
15 Students take Math and Scial Studies
10 Students take English, Math and Social Studies
1.) How many students take English
2.) How many Students take math only
3.) How many Students take English, social studies but not math
4.) How many students take math and social studies but not English class
5.) How many do not take any class.
Click here to see answer by marcsam823(57)

Question 126550: A rectangle has a perimeter of 208 cm. The length is twice the width. Find the dimensions of the rectangle.
Click here to see answer by checkley71(8403)

Question 126518: y=5x
Click here to see answer by checkley71(8403)

Question 126416: On the first part of a trip to Carmel traveling on the freeway, Marge averaged 50 mph. On the rest of the trip, which was 10 mi longer than the first part, she averaged 50 mph. Find the total distance to Carmel if the second part of the trip took 30 min more than the first part.
Click here to see answer by ankor@dixie-net.com(15645)

Question 126496: Please show me how to solve this problem ( it was a homework problem (1 complete problem) and I didn't know where to start). thanks!
200 Students
70 Students take English class
54 Students take Math class
45 Students take Social Studies
28 Students take English and Math
19 Students take English and Scial Studies
15 Students take Math and Scial Studies
10 Students take English, Math and Social Studies
1.) How many students take English
2.) How many Students take math only
3.) How many Students take English, social studies but not math
4.) How many students take math and social studies but not English class
5.) How many do not take any class.
Click here to see answer by Edwin McCravy(8893)

Question 126679: X+25-8/Y (y=5)
Click here to see answer by checkley71(8403)

Question 126714: the resistance(R) of a wire is directly proportionnal to the lenght(L) and inversely proportional to the diameter(D) since a wire to 3 metres long with a diameter of o,25 centimetre has a resistance of 12 OHMS, calulate the length of a wire diameter of 0,3 centimetres and a resistance of 20 OHMS
Click here to see answer by stanbon(57282)

Question 126713: the time(T) required to build a house is inversrly proportionnal to the number of employees working there(E). 5 knowing that workes can build a house in 6 days, how long this would take a 3 workes
Click here to see answer by stanbon(57282)

Question 126712: the time(T) required to perform a some distance by car is inversely proportionnal to the velocity(V). knowing that a some distance has been covered in 6 hours has an average speed of 90 km\h, how fast would it take to make this ride same journey in 5 hours
Click here to see answer by stanbon(57282)

Question 124191: This is another one that has me stumped.
Please solve:
1+(a/b) / 1-(a^2/b^2)
Thanx for your help!
Click here to see answer by solver91311(16872)

Question 126708: the resistance(R) of a wire is directly proportionnal to its lenght(L). knowing that for a wire 10 metres, the resistance is 0,03. calculate the lenght of yarn whose resistance is 0,36.
Click here to see answer by checkley71(8403)

Question 126789: Please help! im so confused! I have tried by substitution and elimination but i just cant get it!!!
2. t+m=2.1
2t+3m=5.15
3. 4o+5a=2.00
3o+4a=1.56
7. 2l+2w=160
2.5r+8b=137
Click here to see answer by solver91311(16872)

Question 127011: how do you solve each system by substitution?

Click here to see answer by solver91311(16872)

Question 126951: 3x+2y=26
Click here to see answer by checkley71(8403)

Question 127078: You have a total of 25 coins, all nickels and quarters. The total value is $3.85. Write and solve a system of equations to find the number of nickels n and the number of quarters q that you have.
Click here to see answer by checkley71(8403)

Question 126950: 3x+2y=26
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